LG NP8340, Service Manual

Page: 23 / 55

3-4
ONE POINT REPAIR GUIDE
3. IF NOT BOOTING WHEN YOU TURN ON THE SET.
3-1. IC802 (NO 1.5 V / 1.2 V)
3-1-1. Solution
Replace IC802 on MAIN board.
3-1-2. How to troubleshoot (Countermeasure)
1) Please Check 5.2 VA of L803 (VIN).
2) If 5.2 VA is abnormal, follow the stage 2-1 at the previous page.
3) If 5.2 VA is OK, but 1.5 VA is abnormal at the IC802 (Pin11, Pin12), check the PWR_CTRL1’s level.
If level ishigh, checkthe around parts (R821, R820, R819, L809) and if there’s no defective component,
replace IC802.
If the PWR_CTRL1 level is Low, follow the stage 7-1.
4) If 5.2 VA is OK, but 1.2 VA is abnormal at the IC802 (Pin9, Pin10), check the PWR_CTRL1’s level.
If level ishigh, checkthe around parts (R833, R832, R831, L810) and if there’s no defective component,
replace IC802.
If the PWR_CTRL1 level is Low, follow the stage 7-1.
3-1-3. Service hint (Any picture / Remark)
< Main board top view >
IC802 IC802