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3-8
ONE POINT REPAIR GUIDE
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.
4-3. SERIAL FLASH (IC503)
4-3-1. Solution
Please check and replace IC503 on MAIN board.
4-3-2. How to troubleshoot (Countermeasure)
1) If the crystal (X501) does oscillate, check serial flash (IC503) on MAIN board.
Check pin8(VCC), pin6(CLK), pin1(CS#), pin2(DO), pin5(DI) of below waveform.
2) If pin1, 2, 5, 6, 8 doesn’t come out, check damping resistor (R511, R513, R514, R515) of IC503.
If damping resistor of IC503 is OK, then replace IC503. (it need to download program)
3) After change IC503, if It is still not below waveform, check IC501(DSP IC).
4-3-3. Service hint (Any picture / Remark)
VCC
CLK
DO
CS#
< Signal check point >
< Signal waveform >
Summary of Contents for CM9730
Page 11: ...MEMO 1 10 ...
Page 13: ...MEMO 2 2 ...
Page 59: ...MEMO 3 42 ...
Page 83: ...3 89 3 90 2 MAIN P C BOARD TOP VIEW ...
Page 84: ...3 91 3 92 MAIN P C BOARD BOTTOM VIEW ...
Page 85: ...3 93 3 94 3 VFD P C BOARD ...
Page 86: ...3 95 3 96 4 MAIN VOLUME P C BOARD 5 MIC P C BOARD ...
Page 87: ...3 97 3 98 6 JOG P C BOARD 7 USB P C BOARD 8 TUNER P C BOARD ...
Page 89: ...3 101 3 102 MEMO MEMO ...