S(Shut Down) Protection - LG SJ3 Service Manual

8. S(SHUT DOWN) PROTECTION

8-1. Solution
Replace IC703 (AMP IC) on MAIN board.
8-2. How to troubleshoot (Countermeasure)
1) Check PVDD voltage (24 V) of IC703 pin36, 37, 38.
- If PVDD voltage has 8.5 V under, refer to "1. NO POWER PROBLEM (PVDD)" on page 3-2.
2) Check GVDD, VDD voltage (12 V) of IC703 pin1, 2.
- If GVDD, VDD voltage has 8.5 V under, refer to "2. POWER ON ERROR" on page 3-3.
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 IC703 (AMP IC) on MAIN bottom board.
8-3. Service hint (Any picture / Remark)
ONE POINT REPAIR GUIDE
IC703 IC703
< MAIN board bottom view >
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