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3-12
ONE POINT REPAIR GUIDE
2. NO BOOTING WHEN POWER ON THE SET
The set doesn’t work when press the power button on the front board or the remote
control.
2-1. FLASH MEMORY (IC101)
2-1-1. Solution
Please check and replace IC101 on MAIN board.
2-1-2. How to troubleshoot (Countermeasure)
1) Check the 3.7 VA to CN102, CN103, and CN104 in standby mode.
If there is no 3.7 VA, check the SMPS.
2) Check 5.6 VA, 12 VA, FL+, FL- and 32 V when power on the set.
- If the set doesn’t work regardless of what the KEY1 changes high to low while pressing the power
button. X100 and X101 work normally but, if you can not power on the set, replace the IC101 with a new
one on the main board.
2-1-3. Service hint (Any picture / Remark)
w~ yj{ys
OyX[`P
XWW
O`UZ_ZWto¡P
XWX
OZYU^]_ro¡P
rlX
OX\P
< Signal check point >
Summary of Contents for CM7420
Page 13: ...1 12 MEMO ...
Page 15: ...2 2 MEMO ...
Page 19: ...A60 4 SPEAKER SECTION FRONT SPEAKER CMS7520F ...
Page 82: ...3 79 3 80 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Page 84: ...3 83 3 84 2 MAIN P C BOARD TOP VIEW ...
Page 85: ...3 85 3 86 MAIN P C BOARD BOTTOM VIEW ...
Page 86: ...3 87 3 88 3 FRONT_VFD P C BOARD TOP VIEW BOTTOM VIEW ...
Page 87: ...3 89 3 90 4 FRONT_MIC PORTABLE P C BOARD TOP VIEW BOTTOM VIEW ...
Page 88: ...3 91 3 92 5 FRONT_VOLUME P C BOARD TOP VIEW ...
Page 89: ...3 93 3 94 FRONT_VOLUME P C BOARD BOTTOM VIEW ...