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Troubleshooting
1. General Features
No. Symptom Cause Check Point

1 No screen Input error of inverter connector 1) Bend the pin legs of P802B connector -> recheck
them
2) Check and repair the IC806,807 SI4925,IC801
SI786,IC803 SI4808.
P502 and Pin 21 connector 1) Check and fix P503B connector
being slipped out 2) Check and fix the components at P502 LCD module
and at main board.
3) Check Pin50.
Cracked components and 1) Check and repair tuner board and main board
soldering at tuner board 2) Solder Q101.
2 Dark screen 1) Defective LCD lamp 1) Replace the inverter
2) Defective inverter 2) Replace the LCD lamp
3) Input error of inverter connector 3) Check the connector input.
3 Broken OSD display Defective the font rom of IC501 Check and replace the font rom of IC508


2. TV and external input
No. Symptom Cause Check Point
4 No sound Defective Reset IC of IC902 1) Check volume and speaker
- Speaker Defective MSP3410D of IC901 - Sound comes out only when being inputted into Audio
- Earphone Defective B+(8V,5V) of IC903,904. L/R
2) Check after replacing IC902
3) Replace IC901
4) Check and replace B+ of IC903,904.
5 Video color beat noise Soldering IC201 and IC502,IC501 Check and resoldering.
or masking it short.
6 Video Jitter P501B Pin20 connector defective. Check the P501B Pin20 connector and repair.




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