Booting In Cd/Usb Function - LG CM8460 Service Manual

8. 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.
8-1. NO DVCC_3.3V, 1.2 VA
8-1-1. Solution
Please check and replace IC505, IC500 on MAIN board.
8-1-2. How to troubleshoot (Countermeasure)
1) Check voltage of IC505 pin3 on MAIN board.
  If IC505 pin3 (about 4.9 V) & D500 Input 5.6 VA doesn't come out, check 5.6 VA from SMPS board.
2) If IC505 pin3 (about 4.9 V) is normal, check the PWR_CTRL(IC505 pin2) is HIGH (about 3.3 V).
  If PWR_CTRL isn't HIGH, check pin B2 of IC501 & R559, R522.
3) If PWR_CTRL is HIGH, check R559 and if there's no defective component then replace IC505.
4) If 3.3 V (DVCC_3.3V) is normal, check 1.2 V output (pin2) voltage of IC500.
  If 1.2 V of IC500 pin2 doesn't come out, then replace IC500.
8-1-3. Service hint (Any picture/ Remark)
ONE POINT REPAIR GUIDE
< MAIN board top view >
IC505 IC505
< MAIN board bottom view >
IC500 IC500
3-9