LG SKC9 - Page 50

3-13
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< MAIN board top view >
IC710
IC710
IC707
IC707
IC708
IC708
IC706
IC706
ONE POINT REPAIR GUIDE
PROTECTION ERROR
No display or No Sound.
3-2. S(SHUT DOWN) PROTECTION
3-2-1. Solution
Replace MAIN board.
3-2-2. How to troubleshoot (Countermeasure)
1) Check PVDD voltage (20 VA) of IC706, IC708, IC707, IC710 pin17, 18, 19, 31, 32.
- If PVDD voltage has 20 V under, refer to STEP 1-1.
2) Check impedance (4 Ω) of speaker unit.
- If impedance of speaker unit has 1 Ω under, replace speaker unit.
3) If check point 1), 2) is ok, replace MAIN board.
3-2-3. Service hint (Any picture / Remark)