Daewoo 21Q4 CRT Television User Manual


 
40
Trouble Shooting Charts
1. NO RASTER
CHECK MAIN B+(+123V/+110V) LINE
NORMAL
NORMAL
NORMAL
ABNORMAL
ABNORMAL
ABNORMAL
ABNORMAL
ABNORMAL
ABNORMAL
ABNORMAL
ABNORMAL
NORMAL
NORMAL
NORMAL
NORMAL
CHECK / REPLACE I701
CHECK / REPLACE
I802(TDA8138)
I803(KA7808)
CHECK / REPLACE
D813 (BYV95C)
D814 (BYV95C)
R824 (2W 43)
Q802 (KTC 3198Y)
Q803 (KTC 3198Y)
T801 (TSM-4245A)
CHECK VOLTAGE AT
(+) OF C807(220µF 400V)
310Vdc AT AC 220V
CHECK / REPLACE F801
FUSE(T4A 250V)
CHECK / REPLACE
D801~D804(1S1888X4)
R803(10W 3.3OHM)
CHECK / REPLACE
I801(STR-S5707)
& PERIPHERAL
COMPONENT
CHECK /REPLACE
I804(PC817)
D812(BYW 95C)
R814(2W 56K)
CHECK POWER SWITCHING
VOLTAGE AT PIN 43 OF I701
*POWER ON; HIGH
*STAND-BY ; LOW
CHECK VOLTAGE(+5V DC)
AT PIN 11 & PIN 37 OF I701
CHECK SDA(PIN 3)
& SCL(PIN4)
WAVEFORM OF I701
CHECK / REPLACE
X701(20MHz, 18MHz)
CHECK / REPLACE
R410(1/4W 3.9)
1401 (2SD1207)
T401 (TD-10A2)
Q402 (2SD2499)
CHECK / REPLACE
T402 F.B.T
& CRT
OK
OK
CHECK HEATER VOLTAGE,
VIDEO B+(200V) LINE,
16.5V & 48V LINE
CHECK HORIZONTAL
DRIVE PULSE AT PIN 40
OF I501(TDA8374A)
[REFER TO WAVE
FORM
]
CHECK HORIZONTAL
Vcc(+8V DC) AT
PIN 37 OF I501
CHECK SDA(PIN 8)
& SCL(PIN7)
WAVEFORM OF I501
CHECK / REPLACE
I501(TDA8374A)