LG NP8540 MusicFlow H5, Service Manual

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3-5
ONE POINT REPAIR GUIDE
3. IF NOT BOOTING WHEN YOU TURN ON THE SET.
3-1. IC902 (NO 1.5 V / 1.2 V)
3-1-1. Solution
Replace IC902 on main board.
3-1-2. How to troubleshoot (Countermeasure)
1) Please check 5.2 VA of L902(VIN).
2) If 5.2 VA is abnormal, follow the stage 1-1 at the previous page.
3) If 5.2 VA is OK, but 1.5 VA is abnormal at the IC902(Pin11, Pin12), check the PWR_CTRL1’s level.
If level ishigh, checkthe around parts (R911, R912, R916, R919, R920, R921, L904, L909, C911, C915
C918, C923, C927, C928, C935, C940, C945, C948) and if there’s no defective component, replace IC902.
If the PWR_CTRL1 level is Low, follow the stage 3-3.
4) If 5.2 VA is OK, but 1.2 VA is abnormal at the IC902(Pin9, Pin10), check the PWR_CTRL0’s level.
If level ishigh, checkthe around parts (R909, R910, R915, R922, R924, R923, L905, L910, C910, C912,
C914, C916, C929, C930, C936, C941, C946, C949) and if there’s no defective component, replace IC902.
If the PWR_CTRL0 level is Low, follow the stage 3-3.
3-1-3. Service hint (Any picture / Remark)
< Main board top view >
IC902 IC902