7. IF THERE IS NO SOUND.
7-1. IC307 (NO PWM_3.3V)
7-1-1. Solution
Replace IC307 on MAIN board.
7-1-2. How to troubleshoot (Countermeasure)
1) Please, check PWM_3.3V of IC307 pin6 (VOUT).
2) If PWM_3.3V is abnormal, follow the stage 4-1 (IC309).
3) If 3.7 VA is OK, please check R338.
If it is not high state, follow the stage 9-1 (IC100).
7-1-3. Service hint (Any picture / Remark)
ONE POINT REPAIR GUIDE
< MAIN board top view >
IC307
IC307
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