3-17
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 CM9520
Page 27: ...A60L A60R 4 SPEAKER SECTION 4 1 FRONT SPEAKER CMS9520F ...
Page 28: ...A80L A80R 4 2 REAR SPEAKER CMS9520S ...
Page 29: ...A90 4 3 PASSIVE SUBWOOFER CMS9520W ...
Page 81: ...3 52 9 VFD GRID CURRENT DRIVER Figure 9 joXayZY O wZW P joYaxZWXG l ...
Page 100: ...3 89 3 90 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Page 102: ...3 93 3 94 2 MAIN P C BOARD TOP VIEW ...
Page 103: ...3 95 3 96 MAIN P C BOARD BOTTOM VIEW ...
Page 104: ...3 97 3 98 3 FRONT_VFD P C BOARD TOP VIEW BOTTOM VIEW ...
Page 106: ...3 101 3 102 6 FRONT_VOLUME P C BOARD TOP VIEW ...
Page 107: ...3 103 3 104 FRONT_VOLUME P C BOARD BOTTOM VIEW ...
Page 108: ...3 105 3 106 7 IPOD P C BOARD TOP VIEW BOTTOM VIEW ...
Page 109: ...MEMO MEMO 3 107 3 108 ...