No Booting In Cd/Usb Function - LG CM9730 Service Manual

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.
4-2. CRYSTAL (X501)
4-2-1. Solution
Please check and replace X501 on MAIN board.
4-2-2. How to troubleshoot (Countermeasure)
1) If 3.3 V & 1.2 V is normal, check Reset 'High' of IC501 pin153 on MAIN board.
If MAIN_RESET isn't high, check MICOM (IC101) pin59.
2) If MAIN_RESET is high, check the soldering status of 12 MHz crystal (X501).
3) If the crystal (X501) doesn't oscillate, check R541,R542,C517,C518 around crystal (X501).
If there's no defective component, then replace X501.
4-2-3. Service hint (Any picture / Remark)
R546
IC501
ONE POINT REPAIR GUIDE
< Signal check point >
X501
3-7
< Signal waveform >