Booting When Power On The Set - LG CM4740 Service Manual

2. NO BOOTING WHEN POWER ON THE SET
The set doesn't work when press the power button on the front board or the remote
control.
2-1. FLASH MEMORY
2-1-1. Solution
Please check and replace IC503 on MAIN board.
2-1-2. How to troubleshoot (Countermeasure)
1) Check 5.6 V to CN501 in standby mode.
If there is no 5.6 V, check the SMPS.
2) Check 12 V, F+, F- and PVDD when power on the set.
- If the set doesn't work regardless of what the KEY1 changes high to low while pressing the power button.
X500 and X501 work normally but, if you can not power on the set, replace IC501 with a new one on
the MAIN board.
2-1-3. Service hint (Any picture / Remark)
IC501
ONE POINT REPAIR GUIDE
PWR_CTRL(R53D)
< Signal check point >
KEY1(R542)
3-4