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1. The picture is frayed Fault 1 Check the control TS7618 and R3633 Fault 2 Check capacitor 2496 C2544 C2545 and R3544 synchr module Fault 3 Check the video signal If the line pulse is poorly then change the MF unit All stations show a wavy picture Fault 1 Replace the earthing connection between the plate and the channel selector with wire Contrast cannot be controlled Fault 1 3V at pin 19 of IC7300 Diodes 6486 and 6490 have been measured and seem ok however they must be replaced Fault 2 Check if control voltage at pin 12 of IC7300 changes when you move the contrast regulator If voltage varies replace D6490 BAV21 part no 4822 130 34189 When the volume is loud the picture is wavy vertically in rhythm with the sound Fault 1 Check if the PSU stabilises at 140V loosen diode 6705 and check resistor 3697 The picture does not stand still looks as if its laying next to a station Fault 1 Check the soldering joints on the synchro board 7550 Picture collapse depending on volume Fault 1 Check T7225 and C2153 15uF Poor picture because the appliance keeps searching for channels A good synch pulse is not present on Pin 28 of the tuner Fault 1 Replace electrolytics of 0 47 MF 1 5MF and 47MF in MF section of tuner Picture varies at high volume Fault 1 Check if the 140V remains stable replace R3697 56K MR25 4822 116 51264 White stripes in picture for 2 3 minutes Fault 1 Loss of capacity in C2571 100uF Dark scr
2. Only for sets with prod ident AGO4 and higher Disconnect pin 5 7 of IC 7220 sound endstage 140 V present Replace IC 7220 TDA 1521Q N2 4822 209 73311 Also check soldering points SOPS transformer PSU does not work correctly Voltage runs out of control to approx 170V and then PSU pulsates F3 appears in the display before the pulsating Fault 1 D6690ES is defective U140 ok with mains 160V with 220V mains control range U140 is 145V and more Fault 1 Replace zener diode D6690 5 1V Fault 2 Appliance is on the French standard In the service menu see service manual reprogramme the yellow service pages Set whistles no 140 V Remove connector M17 140 V present Replace TS 7618 2SD1577PH 4822 130 43921 and replace D 6609 BY 228 20 4822 130 41275 and replace D 6610 BYW 95C 20 4822 130 41602 140 V not present Check soldering points of SOPS transformer T5663 and line transformer T5620 Replace TS7687 by 2SC3973B 4822 130 60851 change R3671 into 22 Ohm Swatt 4822 113 41152 and replace TS7685 BC547 4822 130 44257 and replace TS7686 BC369 5322 130 44593 and replace D6690 BZV85 CS5V1 4822 130 31456 Squeaking line transformer power supply and no HT When diode 6644 is disconnected 13 and 13a HT OK S C in 13 circuit Fault 1 Sync IC S C R3638 and 3639 fail Fault 1 Check BF485 BF423 on the RGB board No function R3619 and R3620 fail Fault 1 Capacitor 2609 1 5nF 3kV is defe
3. Fault 1 Replace IC7780 SAA5231 SDA5231 Unacceptable heating time of older picture tubes Fault 1 Add a diode 1N4148 4822 130 30621 in series with diode 6492 This will not effect the lifetime of the picture tube or the set It prevents the video controller muting the picture until the 3 guns are within the same range of emission Hum during switching Fault 1 Remove C 2199 1 5 uF on stereo decoder Hum on standby Note audible in stand by but not in normal operation Fault 1 Replace D 6690 BZV 85 C5V1 4822 130 31456 Fault 2 During production an incorrect value was provided for C2690 The correct value for C2690 is 1uF 50V 4822 124 41282 Back up battery fails regularly Fault 1 Replace back up battery 1 2V part no 4822 138 10138 by improved model Part no 4822 138 10313 In standby noise emitted by the HT power supply transformer 30V in this position standby voltage ok Another transformer has been tried and TV functions Fault 1 Replace 7668 Check in standby function on 6996 40V 6711 3V 6704 5V Check command on base 7685 4VPP on the base of 6686 3 5VPP E3 appears on screen 140V fail Fault 1 Change line transformer Whistles Fault 1 After replacing repair kit E W coil begins to heat up E W IC TDA 4610 fuse 1601 is defective Crackling tick in first half hour No display during tick then display switches to channel 1 Fault 1 Power supply and LF output stage OK Clean spark br
4. Picture present Can be switched on again with the RC and runs ok Fault 1 Resolder mains transformer Check transistors for the 5V and or change Change 7742 7908 7735 7738 and capacitor 2733 82pF Set turns to standby periodically and will not turn back on Fault 1 Check and replace memory IC24X02 4822 209 62098 Power Fuse 1657 is defective and no picture Fault 1 BUT12A is defective The appliance does not function the transformer whistles slightly Fault 1 Fuse F1601 is defective Fault 2 The power supply is set in the safety mode it peeps Check to see if the fault lies in the power supply or in the loading the loading is replaced with a 220V 100W lamp Replace C2609 if the power supply is in order Fault 3 Replace capacitor C2617 2KV The appliance does not function it whistles Fault 1 Change C2609 8 2 1600V Fault 2 The power supply goes to protective mode Check if the power supply or the loading is defective Replace the loading with a 220V 100W lamp If the power supply is ok then change C2659 Fault 3 Check the power supply voltage TS7687 is defective Replace TS7687 BUT12A with 2SC3973B and R3671 with 22R Fault 4 The power supply starts up with difficulties Check the 140V Replace C2670 68uF The power supply fuse and transistor BUT12A are defective about once a week Fault 1 Occasionally the PTC resistor has a short Therefore the fuse blows and the energy in the magnetising coils is
5. dry joints Fault 1 Unsolder the base of the deflector 100W lamp on the collector Test the drive If ok the diode split transformer is defective The power supply stops when the appliance has been switched on Fuse 1601 has been checked Secondary has been unplugged in the same way Fault 1 Check IC7668 CNX62 T7687 BUT12A T6698 BT 151 Check or change the transistors above and below the CNX Check 1N4148 and BYD33D which are short circuited when switched on Lift the 140 to the level of L5697 and connect a power supply input variac mains and increase the input voltage while keeping an eye on the 140V stable and non variable voltage In the event of collapse recheck all the semi conductors Dead Power supply is in safety mode Fault 1 Disconnect connector M17 If 140V is normal replace C2617 between the collector and the earth of the line transistor Capacitor is o c When the voltage becomes more than 140V the BUT explodes Fault 1 When the CE track of the BUT is defective replace the optocoupler When there is a short then replace the following on the primary side all transistors 4 pieces the optocoupler D6617 R3615 and R3619 Fuse 1651 and BUT12A Ref 7687 are defective Fault 1 Note After replacement the fuse continues to blow The positor has also been changed Check all the power supplies Change the following 7687 BUT 12A 7717 BC548C 7686 BC369 7225 BC548C 7685 BC547 7668 CNX62 77
6. only channelled via BUT 12 and the BUT12A fails Fault 2 Replace BUT with 6SC3973 and resistor R3671 with 220hm S5W BUT 4822 130 60851 Resistor 4822 113 41152 The power voltage increases cannot be controlled with pot R3715 Fault 1 Zener diode 6690 5 1 V has a short circuit The power supply does not start up at 210V but at 230V Fault 1 R3606 680K has changed its values No function the power supply hums Fault 1 The sub power supply is missing in the line output stage The raster IC has a short Knocking on the chassis is causing a short The chassis has been resoldered completely Fault 1 Resolder the Sops transformer if necessary bridge the solder joints and the PCB with wire The same applies to the line transformer High voltage BUT11 blows after about 5 minutes Fault 1 Possible causes pitting coil 5634 drive transformer 5634 loose contacts replace BUT11 with BUT12A line transformer drive IC C2609 9 1nF 1600V Replace capacitor C2609 always first Repeated failure of the line output transistor 7618 and or triggering of the thyristor 6698 Check C2609 Repeated failure of T7687 BUT12A Fault 1 Fit 2SC3973B in place of BUT12A and change R3671 from 15R to 22R SW Fault 2 Replace the coil in the drive Fault 3 Replace the load current diode in the collector circuit BU508 is always breaking down Fault 1 Replace capacitor 2609 with a 1500pF 2KV blue type Fault 2 Sync IC is defect
7. option is set correctly position the wiring to the control panel as far as possible from the de magnetizing reel since pick up from this is often the cause of the fault After the option has been selected the store execute button must be pressed again Channel 52 is indicated on all stations although the correct channel has been entered Fault 1 Replace the memory IC Replace wire bridge 6925 with IC2402 and diode 1N4145 Memory is erased Fault 1 After the appliance has stopped for two hours measure the 1925 battery If the voltage is less than 1 1V replace the battery Fault 2 Check CRT holder Memory does not store brightness contrast colour and sound Fault 1 Replace IC7926 PCF8571P and back up battery No channel input possible The display does not switch over to channel Microprocessor for the control panel and back up battery have already been replaced Fault 1 Check PCF8570 and 8571 Fault 2 When changing the battery a very thin pattern near the battery solder lug is o c supply for the PCF memory IC Please check No sound Stations seem to run away 33V voltage is ok Varicap voltage oscillates by approx 0 6V in all ranges Fault 1 Check capacitor 2538 in the video signal path and check the tuner Improve earth connection in the tuner Automatic channel search begins at channel 21 to 70 Lower bands are therefore not available Fault 1 Replace memory Adjust options Stereo signal disappears 189 25MHz only
8. 1 No 140V Remove connector M17 140V present Reconnect M17 remove R3535 If 140V and audio present no picture replace IC7550 TDA8370 part 4822 209 70178 with 4822 209 73309 Black screen when cold Picture appears at the bottom then moves gradually over rest of screen Fault 1 Check capacitor 2571 100uF 25V in front of vertical IC7570 White picture and no sound Ok via scart Fault 1 IF tuner RGB IC8370 replaced Check safety resistor outside module and decoupling capacitor inside Flickering picture Fault 1 Adjust with small pot on IF board and power supply Sound OK Blank screen with flyback lines Stops after few seconds R3400 is damaged After replacing R3400 is damaged again Trans 7480 BF423 Function After operating for sometime the appliance switches off D6490 is open circuit Fault 1 The contrast is set to maximum and cannot be adjusted D6490 is defective There is radiation on the channel selector Fault 1 Tighten the earthing contacts 6X with wire to the cover lid Appliance fails when it has warmed up Fault 1 The tuning capacitor of the line transistor in the line stage is defective 8 2uF 1600V Sometimes the appliance does not switch on Fault 1 When using the mains plug the power supply sometimes does not work Change C2670 68uF The brightness contrast colour and sound commands do not function Fault 1 Check C6922 and IC7900 The display the contrast colour and sound co
9. 1 the following components on TXT decoder must be changed R3772 1K2 R3800 68K R3780 470R and C2780 1OpF Change of Pal Secam for Middle East and Morocco Note Remove 2A wire connections positions 9257 9274 and 9275 from chassis Remove Cs positions 2273 and 2257 from chassis Fit C position 2256 33pF Fit Secam Pal transcoder 4822 212 22367 position 1310 in connectors M10 and M11 Remove 2B chroma decoder Pal position 1300 and replace by chroma decoder Pal Secam part no 4822 212 22352 Pal Secam chroma decoder Note On request and for a fee chassis 2A and 2B can be transformed to Pal Secam B G not for France Replace Pal chroma decoder by Pal Secam chroma decoder part no 4822 212 22352 Button for on off switch Note Orginal button for mains switch code no 4822 410 24878 is no longer available The following can be used 4822 410 24972 Refs of transistors beside the power supply BUT 12 T7686 BC369 T7685 BC547 Voltage and type of memory battery 1 2V 110MA battery part no 482213810138 To improve PB of copy protected videos Change C2544 to 22nF add 3 3uF across C2545 change R3544 to 3 6kohm For optimum results lt or gt C2544 may be required DEFLECT Only one horizontal stripe Fault 1 Check the 26V If this does not work then replace TDA3654 and possibly TDA8370 Fault 2 Occurs after replacing a defective horizontal output stage capacitor Check IC7550 TDA8370 as it could be operating
10. 1830 and TS7856 Fault 2 The teletext decoder is defective The display does not function Fault 1 Check the voltage on pin 12 of T5663 If it varies then change C2726 1500uF The stand by LED on the remote control often flickers without function The sound increases and the display shows F1 or F2 Fault 1 Replace IC X2402 The speakers are defective Fault 1 Resolder the solder joints on the power supply line transformer E3 is displayed and the 140V power supply is low Fault 1 If the 140V is correct check T7742 and T7743 If the 140V is low check the power supply Unplug point 13 of the power supply transformer If the 140V returns to normal check standby thyristor T6727 T7731 and the associated components If the 140V remains low then unsolder R3740 E3 on display and the line BU heats up 140V gets lower Fault 1 Change line transformer E3 on display Power supply and high tension are correct Fault 1 Check the 13V circuit on pins 16 and 22 of IC7900 If there is no 13V check D6644 D3644 R3645 otherwise replace IC7900 E4 on display Fault 1 Check the scart earth Fault 2 Check U1830 and IC7830 Teletext shakes vertically When switching channels the top of the screen momentarily moves horizontally Fault 1 Replace overvoltage protection diode take original and replace C2959 as well as C2958 F3 in display Fault 1 Replace R3644 and R3645 of 13V Possibly the raster as well TXT has swaying S shape
11. 19 BC558C 6690 zener 5 1V 6671 6670 6689 6667 1N4148 Check the following 3679 2 2K 3678 2 7K 3691 3 9 ohm 3686 680K Plug in the TV on a variac and increase the mains voltage Check the 140V should be stabilised If this is not the case check the power supply for a diode which have a short circuit on switch on Also check for resistors which may be in open circuit or have values which are different to the original ones After replacing defective BUT 12 power supply sings for a short time If you pull out the deflection plug the fault is still there If you measure for 140V only 13 5V are present Horizontal power transistor has already been replaced Fault 1 Remove deflection transistor Load 140V lead with 100W lamp Disconnect secondary voltages except 140V If the lamp is burnt PSU is ok if not the PSU is defective Fault 2 If the PSU runs with the lamp check the parallel C s of the BU 8 2 and 1 5nF Otherwise replace drive IC TDA8370 Fault 3 Change C 8 2nF 1600V in the line end stage Fault 4 2 2nF capacitor in the PSU beside the BU is defective R3620 and R3616 are burnt Resistors are in the RC section 140V to the line transformer collector 25D1577 Transistor is ok no s c can be measured Fault 1 Line transformer is defective C1500 2kV is defective All voltages on the secondary side are too low U instead of 140V only 80V Fault 1 Secondary control circuit TS7717 7719 D6715 Optocou
12. 2 in this case though option diode 6866 must be removed Audio control IC TDA8421 In appliances whose serial no begins with AGO7 and higher a new audio control IC TDA8421 was added as a replacement for TDA8420 This IC has the advantage that the control steps in the lower part of the control range are less whereby an agreeable control occurs Note IC TDA8421 can only be fitted in connection with uP MAB8421 W155 in appliances AGO6 or higher The teletext microcomputer chip is changed to type MAB8461P W 196 code No 4822 209 62479 This also applies to CP90 CP110 G90 and G110 Fault 1 This was to prevent continious page header display under certain conditions in the subtitle mode Safety test after repair Note Due to defective components in an appliance capacitors etc parts of the appliance can become charged This cannot be established when an appliance is tested on an isoformer For safety reasons the appliance must also be connected to a non separated socket and then checked that touchable parts aerial external connections etc are not charged Part nos for HT and focus cable locking Desc Part no Locking for HT cable red 4822 417 50225 Locking for focus cable blue 4822 417 50226 VIP TXT decoder with SAA5230 or SAA5231 Note There are two TXT decoders for the 2B chassis one with video processor IC7780 SAA5230 and one with SAA5231 Furthermore SOV codes the SAA5230 to SAA5231 When SAA5230 is replaced by SAA523
13. 220 present Replace IC 7220 TDA 1521Q N2 4822 209 73311 and loudspeaker s Also check soldering points of SOPS transformer T5663 Picture has very bad distortion notches on the sides Noises in the sound In the line end stage all secondary voltages are approx 10 too low Fault 1 Check if the 140V has a power supply frequency hum Filter electrolytic on the secondary is dead Bass control is insufficient Fault 1 After replacing stereo decoder panel by part no 4822 212 22349 check if bass control is insufficient Replace R3174 by a resistor 10K No sound Fault 1 Check pin 28 of TDA8370 if there are 12V then the IC is defective Fault 2 C2179 on Print 1100 is defective Fault 3 Suspect EEPROM X2402 Fault 4 Turn TV off Push and hold open diamond Turn on Open memo colour and change no to 18 using up and down buttons then store Fault 5 Amplifier ok IC on stereo module replaced Check via scart If same problem check mute check signal on pin 9 and 1 of 7220 lt IN gt 6 and 4 lt OUT gt or check audio signal on pin 11 of 1017 power pin 27 13V check 3030 2030 Fault 6 Speaker is s c Redo solder joints on power supply transformer earth solder joint of the 27V Necessary test appliance voltmeter Hum in right speaker when in standby Fault 1 If mechanical hum check C2690 for value 1uF S50V part no 4822 124 41282 No sound with reception of mono transmitters Fault 1 Replace IC7102 U2830B on t
14. 7900 No high voltage Fault 1 Line transformer already replaced 140V ok Drive present Check C2609 C2611 C2612 and C2617 Fault 2 Audio output stage IC is defective Dead 140V at 122V No channel display 20V and 20V read 10ohm to deck Fault 1 TDA1521 audio IC is S C Dead Fault 1 C2670 68nF reads correct with no leakage Replace C2670 Kevin Eley Electronic Services Derby UK Fault 2 Check the degaussing thermistor and the chopper transformer for dry joints Appliance is dead chopper transistor BUT 12 has failed Fault 1 Check chopper transformer for dry joints Appliance is dead Voltage at base of chopper transistor is lowered Fault 1 Check C2670 No picture ans no sound PSU works with approx 1kHz Fault 1 Fault does not occur immediately Check transformer connections mains and horizontal transformer Check C2609 8 2nF part no 5322 121 42532 and C2617 1 5nF part no 4822 122 33467 Fault 2 Fault occurs immediately Fuse 1601 S C in the line end stage At input 1OkV instead of 7kV EHT 28kV 140V and other voltages ok Signal at collector of line BU ok 1200V EHT secondary voltage ok Voltage on base of tripler C2496 30V Focus pot burnt Fault 1 Line transformer and C2496 changed Check 200V on D6638 and 13V on 6644 Replace line transformer by original part If ok suspect tube support Fizzing and smoke Fault 1 Capacitor 1 5nF 2kV 110 version across the line output tran
15. A repair kit is available which consists of Pos No 6610 BYW95C Pos No 2617 1500pF 9100pF 2KV Pos No 6609 BY228 Pos No 7618 BUSO8V Vertical deflection only occurs after a while Fault 1 Deflection pulse present at deflection unit Measure voltage at pin 6 and 8 replace C2571 100uF A defective C2571 can also lead to failure of the vertical IC No deflection adjustment Falls from max to min Fault 1 Replace adjustment pot Line drive is missing Fault 1 Check D6637 R3639 and C2539 Max line amplitude max E W correction no adjustment possible Fault 1 C2609 C2610 L5601 T7599 T7598 C2590 D6603 D6604 changed but fault persists Check C2599 C2597 C2590 2Vpp Suspecte 3595 29V and 26V Linearity fault Approx 10cm of the picture is missing below Fault 1 IC TDA3654 is defective Picture does not synchronise correctly horizontally No sound If appliance runs for approx 2 mins synchonisation appears slowly but still no sound Fault 1 IC TDA8370 is defective Fault 2 Check C2726 C2290 and C2644 COLOUR The picture has a blue glow Fault 1 R3403 180R is defective Positioned on the tube board with a different colour Red R3452 Green R3432 Flyback lines in a certain colour Blurred picture Fault 1 R3403 R3423 or R3443 180K O C Replace with a 0 25W type Green picture with flyback lines Fault 1 Replace focus pot 33K and check resistors 3M3 and 1M3 Convergence proble
16. D6671 D6670 D6690 R3687 R3670 and C2690 to fail Set dead 140V low at 122V and no channel display 20V and 20V supplies read only 10 or 10V to chassis Fault 1 Check the audio output chip TDA1521 for S C 140V supply normal with a 60W dummy load but low with a bright picture Fault 1 Check transistor 7685 BC547 for being leaky Does not start Fault 1 NB due to insufficient bias at base of chopper transistor set refuses to start Bias is provided by R3656 R3657 C2658 R3686 R3687 If ok check C2670 68nF In safety mode In low tension arcing then line BU blows Fault 1 Change TDA8370 even if in low voltage all the commands are ok Failure of the line output transistor 76 and 18 and triggering of the thyristor 6698 Fault 1 Check C2609 Dead 140V supply low Fault 1 Check if TDA1521 S C and C2670 68nF Fault 2 Suspect transistor BC547 7685 Random tripping Fault 1 Check C567 for dry joints Sparks from crowbar protection Fault 1 Check pin 1 of line output transistor for o c PSU shuts down Fault 1 Check D6729 for leak Stuck in standby PSU tripping NICAM SET Fault 1 Check for noise from the faulty EEPROM X2402 BUT12 S C at start up Changed as well as line transformer CNX62 No start up of HT Fault 1 Check if 140V ok If low check T6727 T7731 R3740 T7742 T7743 D6668 If 140V ok check if there is no 13V on pin 16 and 22 of IC7900 then check D6644 D3644 R3645 If ok check IC
17. Picture Raster is empty jumps to protective circuit Fault 1 Electrolytic 2433 470uF is s c Position on the CRT board The picture is white and shows flyback lines The appliance goes to protective circuit Fault 1 D6410 on the picture tube board is defective therefore power supply resistor R3400 200V is defective and probably also R3639 next to the line transformer When changing the bands ie from band 1 4 or 5 to 3 or interband S1 10 there is sometimes no picture Fault 1 Remove the tuner from the chassis Lift off the cover board side Attention Unsolder the soldering tag Solder 2cm bare wire to grounding tags the ends of 2 contact springs Refit the cover and pull the bare wires through the opening of the springs Do not forget to resolder the tag There is no picture or a bad picture with certain programmes Fault 1 The appliance does not adjust the off set channels correctly Check if the serial No starts with AGO or AGO2 Replace micro processor C7830 and fit a resistor between P9 and P8 of plug K4 1K and diode 1N4148 between P13 and P9 and anode of IC7830 on pin 13 If the serial No starts with AG 04 then only fit a resistor on plug K4 Interference in the picture Fault 1 Interference in the picture on one of the VHS channels Press on the compartment lid to see if the picture improves Solder the earthing spring on the lid Fault 2 During high volume the picture changes Check if 140V remains Change R3697 56K
18. Picture only appears after 1 2 mins Fault 1 Picture tube is poor around one cathode To make picture appear more quickly on picture tube board fit same diode in series to diode pos 6492 No picture no sound After 5 mins picture with line sync problem and no sound After 10 mins colour appears on picture but still no sound Fault 1 Check 5V on pin 28 of 7830 12V on pin 22 of 7550 26V on 6646 Sometimes picture is blanked out at beginning of operation Fault 1 Replace electrolytic C2571 100uF which is temperature sensitive Picture shrinks and controls no longer adjust sufficiently when warm Functions correctly for 15 mins when cold Line transistor overheats and sparks Fault 1 FBT 3619 3620 2SD1577 replaced Check or replace 2617 2609 2610 If ok suspect 2599 6603 2509 and 2597 No picture or sound Goes to safety mode Whistling Line transformer ok Fault 1 Check 13V on 3664 If low suspect 2644 2290 If no power supply check 7668 2681 and 2690 Dark picture Fault 1 R2400 on picture tube connecting board O C Therefore UG2 has dropped to 40V Due to this O C pin 19 of the contrast IC IC7300 TDA4480 does not receive the necessary 3V T7488 and zener diode 6480 are defective No picture no sound but there is high voltage Fault 1 No 12V at tuner IF module Safety resistor 6R5 is defective without any obvious reason Picture and sound hum for 10 mins Power BU blows one time out of ten Fault 1 Check on 7618 ba
19. S7610 If necessary check the signal on collector TS7630 Should be stable if not check R3633 Maximum picture width cannot be regulated fuse 1601 is defective Fault 1 Coil 5611 on the main board must be replaced The picture is too wide and cannot be controlled After about 5 min BU508 blows Fault 1 The transistor in the E W unit causes too wide a picture Check T7599 and T7598 E W correction does not function until maximum picture width is set Fault 1 Replace diode 6603 and 6604 No East West control Fault 1 Replace BD234 No East West pincushion correction Fault 1 Check fuses 1601 T7599 T7598 and C2590 E W correction problem Fault 1 Change diodes 6603 and 6604 Check T7599 T7598 and C2590 Fault 2 Check C2617 E W bowing and picture width is too wide Knock sensitive Fault 1 Dry joints at coil 5611 OTHER The display blinks Fault 1 Check IC7830 U1830 The display shows E6 Fault 1 IC7104 must be checked Commands of the remote control do not function but operating the appliance manually is ok Fault 1 Check U1840 U1830 TS7856 and IC7830 The display shows E3 Fault 1 Check U1830 and IC7830 The display shows E5 Fault 1 Check IC7103 TDA8405 then IC7104 TDA8420 Fault 2 Check if the SDA and DCL signals are present and the power supply voltages on the stereo decoder The display shows EO Fault 1 Check IC7925 IC7926 and IC7900 The display shows E1 Fault 1 Check IC7830 U1840 U
20. The audio endstage is defective which occurs with direct current through the speakers No sound display flashes Fault 1 Changing MAB846 SAB TDA8020 and sound IC will not help Check storage IC X2402 and replace Remove TXT decoder and check No sound no picture High voltage and LED from scart is present Fault 1 Fuse 1642 800mA is defective Distorted sound left channel Check relay 1224 No sound on both channels only via scart Fault 1 Measure on stereo decoder IC 7170 pin 2 must be 12V If the voltage is much lower or not present replace electrolytic No sound picture 2179 330uF No sound Stations seem to run away 33V voltage is ok Varicap voltage oscillates by approx 0 6V in all ranges Fault 1 Check capacitor 2538 in the video signal path and check the tuner Improve earth connection in the tuner No sound picture OK Fault 1 Restriction only for sets with prod id AGO4 and higher Voltage on pin 5 7 IC 7220 present Replace IC 7220 TDA 1521Q N2 4822 209 73311 Also check soldering points of SOPS transformer Fault 2 Sound OK via SCART Replace IC 7103 TDA 8405 4822 209 70934 Fault 3 20V and 20V on point 5 and 7 of IC7220 must be checked Check to see if solder point 19 and 22 of T5663 are secure Solder the points on T5663 Fault 4 IC7104 defective on module 1100 stereo decoder Sometimes no sound no picture Fault 1 Restriction only for sets with prod id AGO4 and higher Voltage pin 5 7 IC 7
21. and change TS7685 BC547 4822 130 44257 TS7686 BC369 5322 130 44593 and D6690 BZV85 C5V 1 4822 130 31456 Fault 3 BUT12 in power supply S C Note Resolder converter transformer and check optocoupler CNX62 Does not function well Programme numbers change spontaneously switches to stand by etc Fault 1 Restriction only for 27CE4691 10R Connect brass axis of the flap of the operation knobs to earth Option changed only UHF tuning Fault 1 Restriction only for sets with prod id from AG06 Remove flat cable between connector K4 and M4 of picture tube replace IC 7925 by ST24C02CP 4822 209 62098 and connect a zener diode BZX79 C5V6 from both pin 5 and pin 6 of IC s7925 to earth anodes to earth Teletext faults Does not function Fault 1 Voltage 13V present on connector 6T8 Replace U 1750 TXT decoder general 4822 212 22346 Scandinavia 4822 212 22396 flof and Spain 4822 212 22828 Teletext faults Characters wrong Fault 1 Voltage 13V present on connector 6T8 Replace U 1750 TXT decoder general 4822 212 22346 Scandinavia 4822 212 22396 flof and Spain 4822 212 22828 RF radiation affecting band 2 Fault 1 Service experience has shown that in areas with relatively poor reception of FM radio on band 2 interference can be picked up from the NICAM decoder of a nearby 2B television receiver The following modification to the NICAM decoder panel 1110 can be applied in cases of specific complaint 1 Insulate t
22. attern generator Screen is slightly red with red flyback lines Appliance ran for 2 weeks then green screen Fault 1 Red transistors on the CRT board previously replaced Replace complete board Original Part no 48222122254 Purity fault Fault 1 Decrease contrast and store Check R3492 2K2 Loss of one colour Fault 1 Check depending which colour is missing 3407 3406 3427 3426 3447 3446 All 33k All on crt base Colour is missing Fault 1 Appliance is set to the wrong standard Open the memory and press colour at the same time Switch on appliance Choose option 01 and close memory Note The fault can be caused under certain circumstances by interference in the data line Route the data line away from the picture tube Occasionally no colour Fault 1 Replace colour subcarrier quartz Note Black and white tint is neutral Green picture with flyback Front controls do not function no reception Fault 1 Check 13V on 6644 with oscilloscope If weak check 2290 3643 3644 3290 3935 and 2935 Brief loss of colour during first ten minutes Picture occasionally jumps when fault occurs Fault 1 Check vertical sync and sandcastle pulse for burst sync Also check line transformer AUDIO The sound is bad and crackles Fault 1 C2134 is defective Note No voltage on pin 11 of IC7125 TDA3803A On switch on the speaker rattles and no other function When the speaker switch is pushed the set functions ok Fault 1
23. chassis is tapped Fault 1 Chassis has already been completely resoldered Resolder SOPS transformer again perhaps connect solder points with wire bridges to the print Same thing for line transformer No function PSU sings protective circuit Fault 1 Replace capacitor C2617 in horizontal control 140V only reaches 77V With a power supply voltage of 180 250V only 77V When disconnecting deflection lead approx 85V are set without a load No voltage on pin 1 of optocoupler Fault 1 Disconnect optocoupler from pin 1 Increase variable ratio transformer from OV If 140V can be set with the variable ratio transformer fault is in the secondary range if not it is in the primary range Dead Line BU heats and blows At power up slight whistle in FBT Fault 1 Check if C2617 is split and leaking No function After switching on protective circuit responds Appliance beeps quietly Fault 1 Fuse 1601 315mA and C2609 are defective Resistors R3620 and R3619 are possibly blown R3486 and D6486 burn at switch on Fault 1 Replace line transformer Power supply stuck in the standby mode Fault 1 Check D6729 for being leaky Fault 2 Check crystal X1867 6MHz Set dead BUT12 chopper transistor S C Fault 1 Usually caused by dry joints on the chopper transformer Philips recommend changing BUT12 to 2SC3973B and R3671 to 22R 5W if repeated failure Sometimes when BUT12 goes S C collector to base it can cause T7686 T7685 D6686 D6672
24. ct the IR sensor If everything is ok replace it by 4822 218 20293 and remove the holder of the old sensor It may happen occasionally that a loading program Bootstrap is produced in the collective pick up of the picture tube holder Fault 2 Check the overload protection on the tube board Fault 3 Check F1642 800mA T The commands are blocked intermittently or IC7830 boots or occasionally there are micro breaks in sound and picture or the power supply pulsates intermittently Fault 1 Disconnect the IR sensor If everything is ok replace it by 4822 218 20293 and remove the holder of the old sensor It may happen occasionally that the spark gap in the socket of the CRT occasionally produces arcovers F1642 may also be the cause of these problems No analog functions Audio balancing LED 25CE4570 is lit Fault 1 Replace the buffer battery Appliance had dry joints on the line transformer BU508 AF had s c After replacing transistor it cut out again when switching on although the dry joints which must have been the cause were removed Fault 1 Check C2609 line oscillator IC 7550 Dead E4 displayed Fault 1 EHT ok Add IC 7550 to the table in the documentation which only mentions U1830 and IC7830 for E4 No function Fault 1 Voltage 140V absent Check soldering points of SOPS transformer and line transformer Fault 2 Voltage 140V absent Replace TS7687 by 2SC3973B 4822 130 60851 change R3671 to 22R 5W 4822 113 41152
25. ctive Fault 2 C2609 C2617 T76218 in the PSU are ok Line transformer is s c Fault 3 Coil 5619 is o c and check C2619 Squeaking power supply Ticking sound from power supply when lamp is used for load Fault 1 Transistor 7736 BC558 is leaky Squeaking no picture and no sound Fuse 1601 is defective When replaced fuse blows immediately Fault 1 Check coil 5611 and T7599 and T7598 in E W circuit No 140V HT supply and whistling from power supply Fault 1 Check resistors 3346 and 3347 If defective replace resistors as well as diode 6646 RGP10G of the 26 Part no RGP1OG 4822 130 31201 HT is too high no raster Fault 1 Replace IC7550 TDA8370 SOPS transformer vibrates in standby mode Fault 1 Caused by low burst frequency of SOPS power supply Increase burst frequency by changing C2690 to 680nF Power supply can only be controlled between 145V and 160V Fault 1 Check control circuit CNX 62 zener 6690 5V1 zener 6715 6V2 zener 6668 30V Fuse 2A blows BUT12A OK Fault 1 Usually BUT12A becomes defective when fuse blows Check 4 rectifier diodes replace by BY255 Check R3654 Check C2664 2n2 1000V above BUT for defective drop Leaky or cracked Test with multimeter 2SD1577 fails after approx 20 secs Distorted picture at switch on Power supply OK with 75W lightbulb Fault 1 Replaced line transformer driver transformer and TDA8370 Check HT cable for S C BUT in PSU makes a S C if
26. e TDA8370 sync processor Hum in sound Sound only comes through quite quietly with Chassis 2B version 3 Fault 1 Replace IC7102 U2830B with new type U2829B No picture No sound 140V operating voltge fails Fault 1 IC7550 TDA8370 is defective No sound in PAL Fault 1 Check FM audio signal on pin 9 of IF If ok check pin 4 of IC7102 If ok check on pin 6 and 8 of IC7103 Suspect 1C7103 if nothing on pins 21 and 22 Check 12V on pin 18 of IC7103 White picture and no sound Ok in scart Fault 1 IF tuner RGB IC8370 replaced Check safety resistor outside module and decoupling capacitor inside Sound level increases strongly intermittently Appliance switches to Programme 1 LED on TV is flashing Fault 1 Check HT and power supply Fault 2 Check if IR receiver oscillates Check if IR receiver supplies pulses while LED is flashing Loss of sound Fault 1 Check on print 1100 IC TDA1524A and C2 Crackling from speakers especially after switch on Fault 1 Ground speaker grids If no results replace HT transformer part no 4822 140 10294 No sound and no detection of Stereo Dual Fault 1 Check for presence of AF left and right signals on IC7102 U2830 U2829 on audio module If missing replace IC Power supply voltage on pin 6 12V No sound via tuner OK via SCART Fault 1 Option code is set incorrectly e g to 8 TUNING MEMORY No tuning possible Fault 1 The quartz 1921 4MHz is defective Can o
27. e of bridge 9704 by a resistor 220R Add a resistor 680R between intersection point 9704 and R789 to the ground Replace C2791 by 100uF R3790 by 3K9 and R3792 by 5K6 This Nicam set stuck in standby and the power supply is tripping Fault 1 Check the EEPROM X2402 chip which has to be programmed for the correct option code 26 for a Nicam set and 18 for a non Nicam set Stuck in standby Fault 1 Only works when thyristor 6727 disconected check d6729 Fault 2 Check EAROM X2402 Fault 3 Remove D6734 to disable standby command Replace EEPROM and set with default info 26 for NICAM and 18 for non NICAM Fault 4 Check memory battery Then check standby thyristor TY6727 Check zener ZD6734 4 7V and diode D6729 Note if the appliance does not have a memory battery suspect EEPROM memory IC X2402 Occasionally no start up or only after an extended switching on period Fault 1 C2670 68nF in the base track of the PSU is defective R3684 150R is high resistive Set goes into standby when switched on Fault 1 Check X2402 Green picture with flyback Front controls do not function no reception Fault 1 Check 13V on 6644 with oscilloscope If weak check 2290 3643 3644 3290 3935 and 2935 Wavy picture and no switching into standby Fault 1 Check pins 12 and 13 on the mains switch transformer Also check capacitor 2733 and transistors 7742 7736 and 7908 No switching to standby Red LED on Lines cave in Appliance hums
28. e transformer ok No Nicam sound All other fm sound ok Fault 1 Check IC7925 memory IC and replace Nasal sound ok via scart Fault 1 Check IF module Module ref 482221010295 Poor sound Fault 1 Replaced U2830 TDA8405 and TDA8420 but no result Check pin 2 of IC7170 for 12V If lower replace IC2179 330uF Sound and picture buzz for 10 mins Power BU blows one time out of ten Fault 1 Check on 7618 base 11 Vpp collector 1200Vpp If ok check 13V on 2644 Volume changes with the picture content Sound distorted Fault 1 Stereo decoder IC IC7102 U2830B is defective Wavy picture and hum in sound Crackling in PSU Fault 1 Check C2646 C2644 C2705 C2708 all 1000uF and C2290 470uF Hum in HF sound Ok in scart Fault 1 Change IF capacitors and clean pot The sound is broken up by scart or by the tuner Fault 1 Check the power supply of the LF stage and its filtering and the electrolytics in the audio IF module Fault 1 Check the power supply of the LF stage and its filtering and the electrolytics in the audio IF module Fault 1 Check and replace if necessary C2179 330uF 16V No picture or sound set whistles Fault 1 No 140V Remove connector M17 140V present Reconnect M17 remove R3535 If 140V and audio present no picture replace IC7550 TDA8370 part 4822 209 70178 with 4822 209 73309 High audible tone Fault 1 SMPS and line output transformer with line output transistor Ok Replac
29. een No sound EHT present 140V 13V ok All voltages ok Fault 1 U1830 has been changed If picture takes a long time to appear check C2571 synchronisation IC Change D6570 Fault 2 Check T7480 BC423 T7438 BF485 R3399 and R3400 on the CRT Slow build up of top part of picture Fault 1 Replace electrolytic 2571 raster circuit It takes a long time for picture to warm up and appear Fault 1 Replace diode D6492 1N4148 on picture tube panel by a series connection of 2 diodes Note that this solution will cause colour changes during the warming up of old picture tubes Fault 2 Check 200 If low replace electrolytic 2638 3 3uF part no 4822 124 42182 No picture no sound Displays E4 EHT is normal Fault 1 No raster oscillation Replace TDA8370 Little contrast picture size is a little too small Fault 1 R3496 is defective then 10V at BAV21 is not present After switching on sound is ok Picture only appears after 5 mins No loose contact Fault 1 The cause could be in the vertical deflection Check if the small electrolytics in the middle of the chassis react to the cold When cooling picture should then be blanked out Fault 2 Check CRT for emissions No raster when cold Fault 1 Check C2571 in the secondary On some 2B chassis the picture appears after 5 to 10 mins then stays normal after that Voltage is correct Fault 1 Weak CRT Solder a 0 47uF capacitor or 0 1uF 250V film capacitor on the filament Sound but no p
30. es according to volume Fault 1 Check T7225 and C2153 15uF Picture varies when volume high Fault 1 Check if 140V is stable Replace R3697 Picture cuts out intermittenly Fault 1 Check fuse 1642 No brightness or picture Fault 1 Check T7438 BF485 T7480 BC423 R399 and R3400 on CRT board Dark screen CAD functions the channels are towards 80 No memorization Fault 1 Check SAB3035 on the main board Convergence problem in middle of screen Fault 1 Check according to colour touched T7418 T7438 or T7458 Video and display cut out Only green light stays on Fault 1 Replace IR receiver 4822 218 20293 Picture fades and sound hums 12V ia at 5V Fault 1 Check on 6644 5V Suspect 2290 and 2644 No picture no sound Appliance whistles chirps and emits smoke Fault 1 Replace capacitors on the right beside the high voltage transformer a round blue one and a rectangular yellow one No contrast adjustment Fault 1 Frequently contrast adjustment does not work in chassis 2B eco model 3 This is caused by diode 6490 being replaced by a different type Replace diode 6490 by BAV21 part no 4822 130 34189 Poor contrast and pale picture Fault 1 Check 200V If low replace electrolytic 2638 3 3uF Picture takes a very long time until it becomes bright sound ok Fault 1 Irradiation from the picture tube is poor Control circuit blanks the picture tube Connect in series a diode 1N4148 to D6492 on the picture tube board
31. fective Measure the tuning voltage at ZTK33 Replace SAB No tuning from Band 1 and 3 Fault 1 Option loss in the memory IC Option adjustment First switch off appliance Press buttons Colour and Open memory at the same time while the mains switch is pressed Press buttons for a moment longer Use the channel rocker arm to put indication in the display on 01 Press button Close memory No VHF channels Fault 1 Check the option code of the tuner simultaneously press the keys on the TV store open and saturation then switch on the set On the display you will see the option code and this can be changed with the C P or C P key Store with the store execute key Tuner Option Code FE6165SQ 01 FE681Q 02 FE616Q 03 UV6l6 11 UV616S 09 UV618Q 10 If the memory IC is defective replace with ST24C02CB1 part 4822 209 62098 Memory loss can be prevented with the following changes Add a diode 1N4148 in series with the 5V and pin 8 of the memory IC Connect cathode with pin 8 Also add a capacitor of 22nF between pin 8 and earth Also the flat cable from the control panel to the chassis must be bent away from the picture tube GEOMETRY The picture is not straight vertically Fault 1 The control for east west correction is missing Replace R3591 with a 2 2K potentiometer Adjust with potiometer east west to its optimum The picture is horizontally unstable Fault 1 The picture is fringy Check control T
32. frequency or if there is a leak on 140V or on power supply control D6688 If 140V is correct check the low voltage line and the line transformer secondary The commands are blocked intermittently or IC7830 starts up or occasionally there are micro breaks in sound and picture or the power supply pulsates intermittently Fault 1 Disconnect the IR sensor If everything is ok replace it by 4822 218 20293 and remove the holder of the old sensor It may happen occasionally that the spark gap in the socket of the CRT occasionally produces arcovers F1642 may also be the cause of these problems Occasionally BUT12A blows Fault 1 The solder joint tracks of the power supply transformer are o c Scrape the varnish off the tracks in order to expand the solder joints Raster IC TDA3653AQ constantly goes defective sometimes after a week sometimes 3 weeks Voltages are correct Raster IC TDA3653AQ constantly goes defective sometimes after a week sometimes 3 weeks Voltages are correct When switching on the PSU whistles and in the high voltage unit R3620 blows Fault 1 C2609 D6609 and D6610 were replaced unsuccessfully The line transformer is defective Only use original part Also replace the line oscillator IC which is positioned in front of the line transformer Check the line end transistor BU508 The line end transistor SD1577 short circuits at once when the appliance is switched on Resistors 3620 and 3619 56R blow C2609 has been replaced No
33. he length of print between pin 40 of IC7450 and 9454 Disconnect the tubular 47pF capacitor from the print side of the panel and discard 2 Remove 10uH choke from position 9454 and reconnect between pin 40 IC7450 and 9454 in place of the insulated print Keep the lead between the choke and pin 40 as short as possible 3 Solder a link wire in position 9454 4 Solder a 47pF chip capacitor code no 4822 122 31772 between pins 2 and 3 of edge connector S10 Do not reuse the discarded 47pF capacitor small physical size is essential in this application Poor reproduction of copy protected VHS tapes Some instances have occurred where VCR reproduction of copy protected VHS tapes has been adversely affected by the anti copy signals recorded in the sync period In cases of specific complaint the following modification can be applied 1 Change C2544 47nF to 22nF 4822 122 30103 2 Change C2545 4 7uF to 8uF 3 3uF 4822 124 23109 in parallel with the 4 7uF on the print side 3 Change R3544 1 8K to 3 6K 4822 050 13602 Note Depending on the VCR in use it may be necessary to select a value for C2544 slightly higher or lower than 22nF to achieve optimum results No function Power supply OK Fault 1 TDA 8370 is defective Line output stage is not driven No switching to standby with RC RC OK Fault 1 Check if pin 7 of IC7830 becomes high low at on standby respectively If so check D6734 and transistor 7731 Fault 2 Check pin 12 of l
34. he stereo decoder Code number 4822 209 73756 Note only appliances with serial number gt AG04 With 2B ECO IIC clock audible at min volume Fault 1 Disconnect print path to pin 15 of IC7103 pin 12 of IC7104 and pin 16 of IC7104 on U1100 as close as possible to these pins Reconnect them to each other using an assembly wire Disconnect print path to 1M7 and 2M7 on mono carrier Connect 5K4 on U1900 to R3127 on U1100 using a 2 AD screened cable Connect screened cable to pin 14 of IC7830 on U1900 and pin 15 of IC7103 on U1100 In AM sound slight nasal sound and buzz Fault 1 Replace 100uF at pin 3 and 10uF at pin 14 of TDA2542 in IF module When picture is dark it begins to tremble as does the sound Fault 1 Check the 13V on 6644 if not suspect 2299 2291 2644 20V on 6704 check 2705 if ok check 2537 and 6537 No picture blue screen no sound Fault 1 Check IC7550 TDA8370 Crackling from speaker at switch on Picture rolls vertically Fault 1 Earth speaker grills Sometimes no function or micro cuts in picture sound Fault 1 If symptom disappears after unplugging IR sensor replace it after removing holder Fault 2 Check spark gap on CRT Fault 3 Check fuse 1642 800mAT Picture fades and sound hums 12V is at 5V Fault 1 Check on 6644 5V Suspect 2290 and 2644 No Fault 1 Check 13V on 3664 If low suspect 2644 2290 If no power supply check 7668 2681 and 2690 picture or sound Goes to safety mode Whistling Lin
35. he teletext microcomputer MAB8461P W 107 has been reprogrammed to suppress the page header when subtitles are being received The new version MAB8461P W196 is available from service under code no 4822 209 62479 In cases of specific complaint the new version may be fitted as a drop in replacement Option adjustment In appliances whose serial no begins with AG 06 or higher a new uP MAB8461 W155 a new memory IC X2402 and for appliances with hyperband a new tuner UV616S or a new front end FE616SQ are used The new uP MAB8461 W155 can be fitted in appliances whose serial no begins with AG04 or higher With this processor the required option is no longer selected with wire bridges and or diodes but must be programmed Procedure Switch off appliance With keys Open memory and Colour pressed in switch on appliance In the display a 2 digit figure appears which represents the adjusted option code With the C P or C P keys set the required option code Tuner Front end Code FE616SQ 01 FE618Q 02 FE616Q 03 UV616S 09 FE616SQ NICAM 09 UV618Q 10 FE618Q NICAM 10 UV616 11 FE616Q NICAM 11 FE644 18 FE644 NICAM 26 Press Store key now the appliance stores the option code and starts in the usual way The new memory IC can only be used in connection with the new uP this memory IC is an EAROM therefore the buffer battery fails The new tuner front end can also be used in appliances with the uP MAB8461 W 13
36. hen connecting a loop system to a modern TV A solution is available from the hearing aid suppliers in the form of a specific loop system amplifier which is supplied from the mains and which functions with a scart or phono plug signal On the advice of a specialist a large part of the cost is usually covered by insurance 2B AG06 changes Note Make the following changes to models of 17 08 1988 Part no of memory IC X2402 must be 4822 209 73313 Part no of channel selector FE616SQ 256 must be 4822 210 10325 Correct version 31 10 1988 is supplied under part no 4822 727 16366 Rebuild for Pal Secam not for France Note Replace Pal decoder with Pal secam Upto and including 4822 212 22676 Since AGOS 4822 212 22827 Checking the power supply 1 Remove connector M17 2 Connect a bulb 75 W across C2701 3 Switch on set 4 Bulb lights 140 V present This means power supply is OK Page header suppression Since the BBC changed the CEEFAX format receivers with fastext will display the page header continuously when the set is in subtitle mode page 888 The problem is only observed on BBC recorded programmes with subtitles subtitles on live programmes and on independent television are not affected The BBC have agreed to suppress the header on future recorded subtitled programmes However many programmes are already in the can and could be transmitted at any time with the page header not suppressed To accommodate this t
37. icture horizontal bar 2cm from the top of the tube The picture appears after working for a few mins Fault 1 Check the following when warm and when cold the signal in the synchronisation circuit of the 12C BUS on transistor 7629 BC548C Check filterings eg 2545 4 7pf and AUX PANEL circuit which produces 12V and 13V Sometimes no picture for 20 minutes Sometimes no sound Sometimes there is a picture but with interruptions possibly lines swaying Fault 1 C2582 1500uF is loose on the print Black picture after switching to teletext When switching back the picture slowly comes back Fault 1 Replace diode pos 6490 BAV21 don t use a substitute It takes at least 3 minutes before the picture appears Colour contrast on TDA4580 Y signal is present still no RGB Fault 1 Possibly insufficient emission at the picture tube or the G2 voltage is too low There is no picture when the beam current is too low Red green or blue fly back lines through the picture Fault 1 R3446 R3447 R3425 R3427 R3406 or R3407 may be defective Weak picture Looks like bad picture tube TXT ok Power supply ok Contrast is adjustable but cannot be set properly Fault 1 TDA4580 TDA4510 TDA4565 have been replaced Check beam current Sometimes no sound no picture Fault 1 Voltage 140 V switches off Check soldering points of SOPS transformer T5663 and line transformer T5620 Picture and sound sometimes disappear Fault 1 Restriction only for
38. idge After replacing line transistor appliance begins to whistle Line transistor fails again immediately Fault 1 After replacing line transistor disconnect the 13V If the line output stage then runs IC TDA8370 is defective Begins to whistle after approx 2hrs If switched off then on again it runs again for 2hrs Fault 1 Check solder joints in IF Check C2609 and chip capacitor in the line unit
39. ine transformer for loose contact Starts up but control remains in standby Fault 1 Replace memory IC Memory contents X2402 change at random Fault 1 Fit a diode 1N4048 in the 5V power supply of memory X2402 cathode at pin 8 and fit a capacitor 220nF between pin 8 of X2402 and the earth Bend band cable between control panel and the drive away from picture tube Replace X2402 by ST24C02CP 4822 209 62098 No tuning in switching from UHF VHF Fault 1 It occurs frequently on chassis 2B AG06 or higher with FE616SQ that band II cannot be tuned to some channels when switching from UHF to VHF This is caused by radiation of oscillator to prescaler as a result of a poor earth connection of the tuner top Solder spring connections of tuner top TXT interference Fault 1 TXT faults may occur when aerial signal is deviating causing loss of characters lines in text Replace bridging wire position 9704 by resistor R3798 220R Add resistor R3797 680R between connection 9704 R789 and the earth If peak filter present change C2791 to 100uF R3790 to 3K9 and R3792 to 5K6 E3 in display and line BU heats up 140V falls Fault 1 Change line transformer No picture or sound Goes to safety mode Whistling Line transformer ok Fault 1 Check 13V on 3664 If low suspect 2644 2290 If no power supply check 7668 2681 and 2690 TXT is not correct Fault 1 Incorrect display TXT and lines disappear On TXT decoder replace wir
40. ive Fault 3 Change C2609 C2617 D6609 and D6610 If BU keeps failing also replace line transformer FBT BU 7618 is defective Fault 1 Check solder joints TDA8370s and diodes 6670 6671 6672 and C2670 At first BUT 12 and T7686 defective After replacing 290V on collector of BU but no voltage at base Fault 1 CNX62 replaced Check R3659 150K R3699 120K R3686 680K T7686 BC369 T7685 BC547 Suspect power transformer T7687 BUT12A fails constantly Fault 1 Fit a 2SC3973B in place of BUT12A and change R3671 15R to 22R 5W Line output transistor is defective and thyristor 6698 goes into safety mode Fault 1 Check C2609 BUT 12A is defective Fault 1 There is an open circuit on the track to the power supply transformer Resolder this connection Random start up of the power supply Fault 1 Shunt R3670 with a 47nF If the power supply starts up the value of R3670 has changed E3 is displayed and 140V power supply is low Fault 1 After disconnecting point 13 of the power supply transformer if 140V returns to normal check T6727 T7731 and the associated components If the 140V remains low remove R3740 If the 140V is still low check the power supply If the 140V is correct check T7742 and T7743 E3 on display and the line BU heats up 140V gets lower Fault 1 Change line transformer The power supply is low Fault 1 Remove M17 low voltage line and fit a 220V 150W bulb If the 140V is low check low
41. m in the middle of the screen Fault 1 Check T7418 T7438 or T7458 according to the colour affected After plugging in a defective scart cable there is still only a bluish shimmering picture IC4850 has already been replaced Fault 1 R3407 33k on the CRT board is high resistive Note Fault has no connection with the defective scart cable Occasionally colour saturation Fault 1 Check the sandcastle on pin 9 of IC7550 TDA8370 Check the 26V beam limiter 10V on R3496 then 3 5V on pin 12 of IC7550 TDA8370 R G B pin 1 3 5 of IC7300 TDA4580 Check the 3 5V black level on pin 26 of IC7300 TDA4580 from the tube board Check the value of R3492 2 2K on the tube board Picture takes approx 3 mins to appear Fault 1 Colour contrast on TDA4580 Y signal is present still no RGB Check for insufficient emission at the picture tube or the G2 voltage is too low There is no picture when the beam current is too low No colour screen is pink Fault 1 Replace picture tube board Fault 2 Check C2297 and IC7300 Colour saturation too low in 2B CTI Fault 1 In 2B chassis with CTI circuit colour saturation is lower Change R3261 to 2M7 Colour spots in flat square picture tubes Fault 1 Coloured spots may have several causes namely local dooming defective picture tube malfunctioning of demagnetization or presence of magnetic fields Too often local dooming is said to cause the problem Check the other possible causes with a p
42. nly be programmed between the channels 21 and 69 Fault 1 Reset the storage as follows switch off the appliance then push storage and colour at the same time switch on the appliance and go to with C P and close the storage On certain stations a different channel can be seen blue and yellow waves appear on the picture Fault 1 Resolder the ground connections of the channel selector lid Only UHF functions Fault 1 Turn off the appliance Open the store and press colour at the same time Set the code to 01 and close the store Fault 2 Replace memory IC X2402 and input options Finally move the connection cable from the control panel to the main print as far as possible from the picture tube VHF channels cannot be selected jumps from UHF channel 69 to channel 21 Fault 1 The option is not set correctly Press Store open and Colour plus Set the correct option with CP and then press on Store execute Move away the wiring of the control panel from the degaussing coil The option is dependent on the tuner FE616SQ Option 01 FE618Q Option 02 FE616Q Option 03 The option number is visible in the display Begins on channel 21 Fault 1 Adjust option for the microprocessor Press store open and increase colour button at the same time and the appliance switches on The option appears in the display change this with the CP button dependent on the tuner FE616SQ Option 1 FE618Q Option 2 FE616Q Option 3 If the
43. ntrols do not function Fault 1 Check the 5V power supply at U1830 and the power supply of IC7830 Occasionally the appliance switches off or does not function at all The power unit hums Note The power supply unit runs when the BU horizontal collector is disconnected U1 drops to approximately 70V when the fault appears The power supply hums Fault 1 Capacitor C2609 8 2nF 1500V in the horizontal scanning circuit is defective The stand by LED on the remote control often flickers without function The sound increases and the display shows F1 or F2 Fault 1 Replace memory IC X2402 TXT does not function correctly Possibly perforated TXT head Fault 1 TXT segments and lines disappear completely Replace the bridging wire 9704 with a 200R resistor Fit a 680R resistor between junction 9704 and R789 to ground If present then change C2791 to 100uF R3790 to 3 9K and R3792 to 5 6K Fault 2 Change the storage IC7770 and 7771 on the TXT module After some time the appliance goes into standby During channel search the numbers run through the display very quickly and the appliance remains in stand by Fault 1 Check memory IC or replace TXT stops on page 100 Fault 1 If only page 100 is in the top left hand side of the picture then check IC7780 on the TXT decoder Either commands are blocked intermittently C7830 starts up or occasionally small interruptions in the sound and picture or the PSU pumps now and again Fault 1 Disconne
44. pler 7668 Load at 20V Standby light appears for a sec then nothing The CTV has no sound or picture Battery is ok Voltage on the collector of the transistor is ok Fault 1 In the power supply change CNX82 T7685 T7686 D6690 thyristor 6727 BUT18AF blows even when power transformer replaced Fault 1 7687 BUT12A Check 2681 2690 and 7668 140V goes up to 300V Line output transformer immediately goes defective Fault 1 F1711 D6711 BAV21 open circuit Line output stage does not function The resistors R3619 3620 burn out spontaneously Fault 1 Line transformer is defective when these resistors burn out Stuck in standby Power Supply Part tripping Tries to start up if prog button held in but LED corrupted Restriction From AG06 onwards Fault 1 Tries to start up if prog button held in but LED corrupted Disconnect D7634 and see if set starts up If it does check pulse train on SDA and SCL lines If these lines are stuck or are showing spurious operation replace 17925 EEPROM X2402 type 4822 209 62098 Set hiccups Fault 1 Replace C2609 8 2 nF 4822 121 40249 Protection circuit active set hiccups Fault 1 Remove connector M17 140 V present Replace C 2609 8 2 nF 4822 121 40249 Supply overloaded set peeps Fault 1 Remove connector M17 140 V present Replace TS 7618 2SD1577PH 4822 130 43921 and replace D 6609 BY 228 20 4822 130 41275 and replace D 6610 BYW 95C 20 4822 130 41602 Fault 2
45. se 11 Vpp collector 1200Vpp If ok check 13V on 2644 With brightness at max raster cramps Fault 1 Replace zener diode 6668 30V Wavy picture and hum in sound Crackling in PSU Fault 1 Check C2646 C2644 C2705 C2708 all 1000uF and C2290 470uF Picture takes a while to appear Fault 1 CRT is flat Load CRT Picture is blanked Fault 1 Incorrect pulses from the field output stage Check C2571 in teh field flyback boost circuit note that the value is 68uF with 90 degree sets Zigzags in picture and hum in sound Fault 1 Change T7225 Change C2153 to 15uF Black screen FBT ok After 5 mins white line on lowest third of CRT Fault 1 TDA8370 and TDA3654 replaced 180V on CRT cathodes Via SCART composite signal present at pin 5 of TDA8370 but not on pin 3 SDA and SCL present Change C2571 Fault 2 Use oscilloscope to check 13V on D6644 200V on 2638 and 26V on 2646 Suspect 5V on 7735 Cramped frame horizontally and vertically Fault 1 Fuse 1601 125mA has burnt out Picture blanked by incorrect pulses from the field output stage Picture begins to appear if left on for a long time about two inches from the bottom of the screen Fault 1 C2571 100uF 25 in the field flyback boost circuit Screen switched off at start up Picture appears after 2 mins Sound ok Time base ok Fault 1 Check 2617 If ok check 11Vpp on base of 7618 1200Vpp on collector Suspect G2 voltage No picture or sound set whistles Fault
46. sets with prod id AG04 and higher Replace IC 7830 MAB8461P W 155 4822 209 73465 See service information CT88 34 Picture disappears sometimes Fault 1 Restriction only for PAL sets Picture OK via SCART Replace front end U 1015 FE 616SQ 4822 210 10325 Picture brightness too high Fault 1 Contrast not adjustable Voltage Pin 19 IC 7300 gt 8 V Replace D 6490 BAV 21 4822 130 34189 No picture no sound Fault 1 Voltage 140 V present Check soldering points of line transformer No picture sound OK Fault 1 Voltage on pin 14 of IC 7550 smaller then 2V Replace IC 7550 TDA 8370 V2 4822 209 70178 and replace IC 7570 TDA 3654Q 4822 209 83351 Signal pin 15 17 18 IC 7300 OK Burst key pin 10 IC 7300 OK Replace IC 7300 TDA 4580 4822 209 70018 Fault 2 Replace resistors 3646 3647 111 30494 26V missing Fault 3 Check if the high voltage is present Check if the contrast adjustment works on pin 9 of IC7300 Replace C2496 22nF Picture has very bad distortion notches on the sides Noises in the sound In the line end stage all secondary voltages are approx 10 too low Fault 1 Check if the 140V has a power supply frequency hum Filter electrolytic on the secondary is dead Purple picture after loose connection of brown wire to picture tube base and aquadag coating Colour changes to white with intermittent flyback lines Picture contents in background but distorted then they disappear Fault 1 TDA4580 is defecti
47. sistor has split Replace capacitor However if there is field collapse carry out some meter checks around the TDA8370 timebase generator chip IC7550 No 12V supply at pin 22 which means that the chip is running on its start up supply R3535 10 is O C as C2536 100uF 25V is S C Replace the two items should return everything to normal Ht high will turn down to 159V but no further Fault 1 Replace R3714 3K with 3K9 Appliance is dead faint squealing from power supply Fault 1 R3620 R3619 R3486 and D6486 are burnt Replace line output transistor R3520 R3619 R3486 and D6486 Screaming sound from power Fault 1 By disconnecting thyristor 6698 there is a CA 115V on cathode of D6700 D6701 A microscopical breakage in the print track coming from pin 1 on the line transformer 5563 Fuse 1601 may blow but not necessarily Smokes and makes a hissing noise Fault 1 Defective capacitor in the horizontal ouput stage Incorrect regulation of voltage on 140V line Fault 1 Check transistor TR7685 BC547 for O C or leaks Dead R3670 33R USEFUL INFO Character generator SAA5243P E Note With the chassis 2B AG06 and higher a new character generator IC7760 SAA5243P E has been added to the teletext print Code number is 4822 209 72353 Bracket under line transformer 4822 404 60379 Bracket under line transformer 14822 502 30479 Matching screws Connection of a loop system to the TV Note A problem usually occurs w
48. tube print C2433 470uF defective Gray picture when contrast and brightness are at max No sound or picture via scart Power supply OK Fault 1 Check whether 13V or 13D is present Fault 2 If no display or error indication then no 5V or uP 7836 or CITAC 7900 is defective Black bar in top of picture disappears slowly Fault 1 Replace C2571 raster Picture changes depending on the volume 140V is unstable Fault 1 Replace resistor 3697 56K Loss of picture when switching to certain programmes Fault 1 Check if serial no starts with AGO6 No reception on band 3 when switching from UHF to VHF Solder spring contacts of tuner top to earth pins of tuner print When picture is dark it begins to tremble as does the sound Fault 1 Check the 13V on 6644 if not suspect 2299 2291 2644 20V on 6704 check 2705 if ok check 2537 and 6537 No picture blue screen no sound Fault 1 Check IC7550 TDA8370 Picture pumps flashes buzz in sound Fault 1 IF capacitor replaced without effect Check T7225 and C2153 15uF Check 140V and R3697 Display does not switch off snow sound cuts out Fault 1 Check tuner Necessary equipment oscilloscope Screen saturated in green looks like defective tube Fault 1 R3426 on CRT board is O C No picture sync when changing channel chassis index AGO7 with aerial signal higher than 10mV Fault 1 Mount a transistor to reduce tuner gain when communicating and in channel search Picture flash
49. tween pin 9 4K and pin 8 4K fit diode 1N4148 between pin 13 of IC7830 A and pin 19 of IC7830 disconnect R3839 at pin 9 of IC7830 and reconnect to pin 1 of IC7830 2B ECO AG04 uP part no 4822 209 11611 2B uP W156 part no 4822 209 51459 Will not tune on some channels Fault 1 Will not tune drifts colour disappears or interference on a certain channel e g channel 5 and 59 The cause is a poor earth connection of the screening plate of the channel selecter Solder down the screening plate No or poor tuning of offset channels Loss of colour Fault 1 2B ECO AG04 Replace uP IC7830 by new model add resistor 1K between 9K4 and 8K4 2B replace uP IC7830 by W156 model fit resistor 1KO between pin 9 4K and pin 8 4K fit diode 1N4148 between pin 13 of IC7830 A and pin 19 of IC7830 disconnect R3839 at pin 9 of IC7830 and reconnect to pin 1 of IC7830 2B ECO AG04 uP part no 4822 209 11611 2B uP W156 part no 4822 209 51459 Dark screen CAD functions the channels are towards 80 No memorization Fault 1 Check SAB3035 on the main board Necessary test equipment ocsilloscope Does not tune on channel Channels can be recognised but appliance continues to search Fault 1 Replaced tuner and SAB3035 Replace coil 5555 in IF unit Located on TDA8370 When switching over to another channel station disappears for a short time Possibly pulsating Fault 1 Most of the time the 3 electrolytics in the tuner are de
50. ve TDA4510 red absent but with a little green is defective Black screen blocked tube Fault 1 Check if R3406 3407 3426 3427 3446 3447 33K O C or if they have changed value When switchng on from cold the top part of the picture appears completely black or else with a dark band 6 8 cm high Defect disappears when the appliance warms up Fault 1 Capacitor C2571 100uF 25V in the vertical deflection stage is defective Tube blocks at the dark level Fault 1 Check if diode 6462 on the RGB board is leaky as a result of BF423 and BF485 s c Dark screen with slightly lit horizontal zone at top of picture Spot in middle of screen at switch off Sound ok Fault 1 TDA4580 and TDA4555 replaced but to no avail Replace capacitor C2571 100uF in time base Fit a diode 1N4148 in series with diode 6492 on CRT board Fit a capacitor 0 1uF parallel to 3P13 and 5P15 on CRT connector Failure is caused by CRT drift Fault 2 Check raster circuit 7570 pin 9 27V If missing check 6646 and 2646 If ok check signal on pin 3 2Vpp on pin 5 40Vpp If incorrect suspect 2571 and 7570 Black bar at bottom or no raster Fault 1 Replace electrolytic 2571 Distorted picture when cold in top third of screen Picture gradually returns to normal after 10 mins Fault 1 TDA3654 C2575 and C2571 replaced Check 27V on pin 9 of 7570 13V on pin 22 of 7550 Suspect 2536 2646 White picture with flyback lines Fault 1 3 9V missing on the picture
51. with reception on channel 7 Fault 1 Replace entire stereo module Tuning unstable Fault 1 Tuning voltage of pin 11 U 1015 stable Replace U 1015 FE 616SQ 4822 210 10325 Contents of memory lost Fault 1 Restriction only for sets with prod id A600 A605 The failure occurs when the set is switched off by the power switch Replace battery 1925 4822 138 10313 IC 7925 IC 7926 PCD 8571P 4822 209 83571 No VHF reception Channels start at 21 Fault 1 Set option for uP and place wiring to control unit as far away from demagnetization as possible To set option for uP Press Store Open and Colour Plus simultaneously and switch on Display shows option Change option using Colour Plus keys depending on the tuner FE616SQ option 01 FE618Q option 02 FE616Q option 03 Once option has been set properly place wiring to control unit as far away from the demagnetisation coil as possible Radiation from coil causes the fault After setting the option press Store Execute key Will not tune on some channels Fault 1 Will not tune drifts colour disappears or interference on a certain channel e g channel 5 and 59 The cause is a poor earth connection of the screening plate of the channel selecter Solder down the screening plate No or poor tuning of offset channels Loss of colour Fault 1 2B ECO AG04 Replace uP IC7830 by new model add resistor 1K between 9K4 and 8K4 2B replace uP IC7830 by W156 model fit resistor 1KO be
52. with the start up tension without having full working tension 12V at terminal 22 of CI7550 This could be caused by R3535 10R O C due to C2536 100u 25VCC S C No vertical synchronization in cold conditions approx 10 seconds IC7550 TDA8370 is not defective Fault 1 It is possible that there is a fault in the IF amplifier Defective electrolytics Cool down with freezer if fault then occurs There were once defective electrolytics in the IF Fault 2 Defective tuner IF C2538 is defective Vertical linearity fault Line transformer has already been replaced Fault 1 C2509 on the left beside the LOPT reacts thermically Check T7502 T7503 R3508 3511 R3515 R3523 R3529 C2509 and C2506 Bad synchronisation Fault 1 Check C2144 47uF 4822 124 20699 No raster green line in center Power supply ok Fault 1 Raster amplifier replaced On 7570 check on pin 9 26V on pin 8 14V on pin 6 25V If ok check in signal on pin 3 out signal on pin 5 If ok suspect 2571 2851 3578 and 3579 No raster sync Fault 1 Check C2548 and 26 of IC7550 TDA8370 Linearity and vertical centering are defective Fault 1 Replace C2575 10uF Line output stage transistor blows immediately at switch on Fault 1 R3619 and R3620 56R are also burnt Line transformer is defective Replace by HR6140 Replace line output transistor by S2000AF Replace C2609 Fault 2 Replace C2617 and TDA8370 Failure of line output stage Fault 1

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