S(Shut Down) Protection - LG SH5B Service Manual

10. S(SHUT DOWN) PROTECTION

10-1. Solution
Replace IC702, IC703 (AMP IC) on MAIN board.
10-2. How to troubleshoot (Countermeasure)
1) Check PVDD voltage (24 V) of FB607.
- If PVDD voltage has 8.5 V under, refer to NO POWER PROBLEM guide. (STEP 1-1.)
2) Check GVDD, VDD voltage (12 V) of IC702, IC703 pin1, 2.
- If GVDD, VDD voltage has 8.5 V under, refer to 12 V no power repair guide. (STEP 2-1.)
3) Check impedance (4 Ω) of speaker unit.
- If impedance of speaker unit has 1 Ω under, replace speaker unit.
4) If check point 1), 2), 3) is ok, replace IC702, IC703 (AMP IC) on MAIN bottom board.
10-3. Service hint (Any picture / Remark)
ONE POINT REPAIR GUIDE
IC703 IC703
IC702 IC702
< MAIN board bottom view >
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