LG FH6 Service Manual page 32

4. NO SOUND
"No USB" message is displayed on VFD, in the USB function.
4-1. USB FUNCTION
4-1-1. Solution
Check IC306 on MAIN board.
4-1-2. How to troubleshoot (Countermeasure)
1) Check USB_5V of CN102 (pin7, 8, 9).
If USB_5V is abnormal, check IC306 and IC305.
2) If USB_5V is OK, check USB_DN, USB_DP signal of CN102 (pin13, 15).
- Check JK401 on DJ KEY board.
- Check CN102 on MAIN board and CN401 on DJ KEY board connection.
- Check C120, C121 on MAIN board.
3) ) If problem still occurs, check IC501 (MCS IC).
4-1-3. Service hint (Any picture/ Remark)
IC305 IC305
(TJ4320) (TJ4320)
ONE POINT REPAIR GUIDE
C120, C121 C120, C121
CN102 CN102
(TO DJ KEY) (TO DJ KEY)
< MAIN board top view >
IC306 IC306
(BD2242) (BD2242)
< MAIN board bottom view >
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