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ONE POINT REPAIR GUIDE
3. PROTECTION ERROR
No display or No Sound.
3-1. D(DC) PROTECTION
3-1-1. Solution
Replace AMP board.
3-1-2. How to troubleshoot (Countermeasure)
1) Check DC Voltage of speaker out FL+/-, TL+/- (CN703 pin1, 2, 3, 4), FR +/-, TR+/- (CN704 pin1, 2, 4, 5),
and C+/- (CN702 pin1, 2).
2) Check resistor crack, cold solder of PWM IC out (AR606, AR607, AR608).
3) Check speaker cable’s abnormal.
4)
If PWM IC out is ok and speaker out (FL+/-, FR+/-, TL+/-, TR+/-, C+/-) has DC voltage, then replace AMP board.
3-1-3. Service hint (Any picture / Remark)
< AMP board bottom view >
CN704
CN703
CN702