3-18
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.
4-4. SDRAM (IC502)
4-4-1. Solution
Please check and replace IC502 on MAIN board.
4-4-2. How to troubleshoot (Countermeasure)
1) Check below waveform & soldering status of SDRAM (IC502) on MAIN board.
If pin17(#CAS), pin18(#RAS), pin19($CS), pin38(CLK), pin29(address), pin2(DQ) doesn’t come out,
check damping resistor (R508,R506,R504,R507).
2) If resistor is OK, then replace IC502(SDRAM).
3) After change IC502, if It is still not below waveform, check IC501(DSP IC).
4-4-3. Service hint (Any picture / Remark)
} jj
y
V jz
y hz
V ~ l
jhz
< Signal check point >
< Signal waveform >
Содержание CM9520
Страница 27: ...A60L A60R 4 SPEAKER SECTION 4 1 FRONT SPEAKER CMS9520F ...
Страница 28: ...A80L A80R 4 2 REAR SPEAKER CMS9520S ...
Страница 29: ...A90 4 3 PASSIVE SUBWOOFER CMS9520W ...
Страница 81: ...3 52 9 VFD GRID CURRENT DRIVER Figure 9 joXayZY O wZW P joYaxZWXG l ...
Страница 100: ...3 89 3 90 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Страница 102: ...3 93 3 94 2 MAIN P C BOARD TOP VIEW ...
Страница 103: ...3 95 3 96 MAIN P C BOARD BOTTOM VIEW ...
Страница 104: ...3 97 3 98 3 FRONT_VFD P C BOARD TOP VIEW BOTTOM VIEW ...
Страница 105: ...3 99 3 100 4 FRONT_USB P C BOARD TOP VIEW BOTTOM VIEW 5 FRONT_MIC P C BOARD TOP VIEW BOTTOM VIEW ...
Страница 106: ...3 101 3 102 6 FRONT_VOLUME P C BOARD TOP VIEW ...
Страница 107: ...3 103 3 104 FRONT_VOLUME P C BOARD BOTTOM VIEW ...
Страница 108: ...3 105 3 106 7 IPOD P C BOARD TOP VIEW BOTTOM VIEW ...
Страница 109: ...MEMO MEMO 3 107 3 108 ...