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ELECTRICAL TROUBLESHOOTING GUIDE
10. DOUBLE USB FUNCTION
USB FUNCTION
Check USB jack
(CN301/ CN302).
Replace IC500.
Check CN301.
Check IC500
(Pin U7, U8/ A7, A8).
Display “NO FILE”.
Check USB_5V.
Display “READ”.
Plug-in USB device.
Display “NO USB”.
Check
USB1_D-/D+(R335,336)
USB2_D-/D+(R301,
302).
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
Check USB audio file in USB device
(MP3, WMA file is playable)