14B2-TX/20B2-TX
21B2-TX
YESNO
Check IC801.
Check IC801 and its related circuit.Check Q204 and its related circuit.
YESYES
No snow noise.Check Q301, pins (4) and (6) of IC801 and peripheral circuit.
(Continued)Does signal appear at pin (28) of IC801?
NONO
Does signal appear at pin (40) of IC801 ?Check C356 and peripheral circuit.
Does signal appear at pin (38) of IC801 ?Check pin (1) of SF201 and Tuner's related circuit. Check pin (37) of IC801 and related circuit.
NONO
18-2
NO SOUNDYES (Signal)YES
Does the noise level increase at max. Contrast, Brightness and Sound controls ?
NO PICTURE, NO SOUND
Does signal appear at pin (44) of IC801 ?Does signal appear at pins (6) and (8) of IC301 ?Check P301 connector of IC301 and peripheral circuit.
Abnormal
Check pin (27) of IC801, Tuner and related circuit.
Normal
Check the tuner AGC at TP201.
Normal
Noise increases but no signal is received.
Check the tuner supply voltage LB must be approx. 5V. BT must be approx. 32V and CH preset data check.Check pin (38) of IC801.
Sound system pins (28) and Sound Detector Circuit. Sound Switch and Att. Audio Output Circuit.
CIRCUITS TO BE CHECKED: Tuner. PIF. Automatic Gain Control. (5V), (33V) Power Source.CIRCUITS TO BE CHECKED: � (44) of IC801. �� Control. �
Checking the protector circuit.
NO
Normal
Blown out.
ON/OFFON
Replace the fuse.
Check IC701, D701 and C707.
D1001 (Power LED Green) turns on.D1001 (Power LED Red) turns on or turns ON/OFF.
The fuse is blown out again.
YES
2s0.5s
AbnormalCheck IC801.
YES18-1
NormalNormal
Check F701.
NO RASTERCheck CRT connector K1-K5 bias.Check C878.Does horizontal circuit oscillate ?
Check Secondary Main+B T701 pin (17) voltage (Approx. 115V)Normal
Check T701 pin (7) voltage (Approx. 310V at 220V AC)Check IC801, IC751, D605 and Q601.
NO
IC1003 (M24C08)IC801 (IX3412CE)IC401 (M52797SP)TU201 (VTST5HD84)
TROUBLE SHOOTING TABLETROUBLE SHOOTING TABLE
V/C/JAV SwitchPLL Tuner
If a bus error happens, the LED RED [pin (11) of IC801 LOW] indicator starts blinking and the power is turned off. The power key (CHANNEL button on the TV) is still effective.
Normal
AbnormalAbnormal
Bus error mode See Fig.1
Check R701, R707 and D709.Check R615 and R618.Fig.1EEPROM
Check D758, IC702, IC753 and R712.
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