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3-13
< Fronnt - VFD board bottom view >
ONE POINT REPAIR GUIDE
3. VFD IS NOT DISPLAYED WHEN POWER ON THE SET
When power on the set, any icons or characters on VFD are not displayed.
3-1. VFD
3-1-1. Solution
Please check and replace DIG301 on FRONT board.
3-1-2. How to troubleshoot (Countermeasure)
1) Check if VKK(-32 V), FL+ and FL- are output from SMPS to VFD via the main board.
2) Check if 3.3 VA enters IC301.
3) Check if the IC101 outputs VFD_RST, VFD_CLK, VFD_STB, and VFD_STB to the front board.
4) Check if pin P1~15G of DIG301.
If there is no signal, replace IC301 with a new one.
If there is no problem, replace VFD with a new one.
3-1-3. Service hint (Any picture / Remark)
3.3 VA
IC301
VFD_CLK
VFD_STB
VFD_RST
Содержание CM7420
Страница 13: ...1 12 MEMO ...
Страница 15: ...2 2 MEMO ...
Страница 19: ...A60 4 SPEAKER SECTION FRONT SPEAKER CMS7520F ...
Страница 82: ...3 79 3 80 PRINTED CIRCUIT BOARD DIAGRAMS 1 SMPS P C BOARD TOP VIEW ...
Страница 84: ...3 83 3 84 2 MAIN P C BOARD TOP VIEW ...
Страница 85: ...3 85 3 86 MAIN P C BOARD BOTTOM VIEW ...
Страница 86: ...3 87 3 88 3 FRONT_VFD P C BOARD TOP VIEW BOTTOM VIEW ...
Страница 87: ...3 89 3 90 4 FRONT_MIC PORTABLE P C BOARD TOP VIEW BOTTOM VIEW ...
Страница 88: ...3 91 3 92 5 FRONT_VOLUME P C BOARD TOP VIEW ...
Страница 89: ...3 93 3 94 FRONT_VOLUME P C BOARD BOTTOM VIEW ...