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ONE POINT REPAIR GUIDE
NO SOUND
There is no sound output in the USB Function, repair the set according to the following guide.
6-3. USB FUNCTION
6-3-1. Solution
Replace IC204 on MAIN board.
6-3-2. How to troubleshoot (Countermeasure)
1) Check +5V_USB to USB board.
If the USB LED are turned on, the voltage is okay, if so not, check USB_5V to pin4, 5 of CN803.
2) Check USB D1± or USB D2± from MAIN board to TOP board.
a. Check 2.0_D1±signals(pin U7, U8 ) or 1.1_D1± signals(pin A7, A8 ) to IC501.
b. Check USB± signals to CN502(pin1, 2, 7, 8).
If there is any trouble, check the power for IC207.
The power is normal but, if the signal waveform to the IC is distorted or no signal,
replace it with a new one.
3) Check if “Digital audio AMP block” on item 6-1 is normal.
6-3-3. Service hint (Any picture/ Remark)
USB D-/D+ (CN502 pin1, 2 & pin7, 8)
< Waveform of USB D± signal >
D
D+
D-
< MAIN board top view >
CN502
CN502
IC501
IC501