LG OM7560 Service Manual page 25

4. NO BOOTING (IN CD/USB FUNCTION)
After you turn on power key and displayed message in the following order (HELLO  VOL XX 
CD or USB) on VFD, it will not display other message on VFD, and it will not boot-up normally.
4-1. NO DVCC_3.3V, 1.2 VA
4-1-1. Solution
Please check and replace IC202, IC205 on MAIN board.
4-1-2. How to troubleshoot (Countermeasure)
1) Check Voltage of IC202 pin3 on MAIN board.
  If IC202 pin3 (about 5.1 V) & pin1 Input 12 VA doesn't come out, check +12 VA from SMPS board.
2) If IC202 pin3 (about 5.1 V) is normal, check voltage of IC205 pin3 (about 1.2 VA), pin6 (about 3.3 VA).
If IC205 pin3 (about 1.2 VA), pin6 (about 3.3 VA) doesn't come out, check R253, R254, R256 and R260, R261, R262.
If there's no defective component then replace IC205.
3) PWR_CTRL is high, check R512 and if there's no defective component then replace IC505.
PWR_CTRL (IC505 pin3) is high (about 3.2 V)
  If PWR_CTRL isn't high, check pin D11 of IC501 & R512, R513
4) If PWR_CTRL is high, check R559 and if there's no defective component then replace IC505.
4-1-3. Service hint (Any picture/ Remark)
ONE POINT REPAIR GUIDE
< MAIN board top view >
IC505 IC505
< MAIN board bottom view >
IC205 IC205
IC202 IC202
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