LG SL8YG Service Manual page 72

3. How to Duplicate Problem
Wireless rear speaker doesn't output a sound.
3-1. Solution
Replace AMP board (No 3.3 V).
3-2. How to troubleshoot (Countermeasure)
PWM 3.3 V
(RIC307 pin3)
no output.
NO
Check Module or connection.
3-3. Service hint (Any picture / Remark)
RIC307 RIC307 RIC307
< AMP board top view >
ONE POINT REPAIR GUIDE
YES
(RIC307 pin2)
Replace AMP board.
RIC308 RIC308 RIC308
5 VA
YES
no input.
NO
5-5
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Replace SMPS board.
Only for training and service purposes.