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3-5
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 VFD300 on FRONT board.
3-1-2. How to troubleshoot (Countermeasure)
1) Check if 12 VA is output from SMPS to VFD via the MAIN board.
2) Check if Check if LED_5 V, DVCC_3 V output from the MAIN board.
3) Check if IC500 outputs VFD_D0, VFD_CLK and VFD_STB to the FRONT board.
4) Check if VFD300 output SW signal to the FRONT board.
If the SW signal isn’t output, replace VFD300 with new one.
5) check if Q300 and Q301 to the FRONT board.
If the VH signal isn’t output, replace Q300, Q301 with new one.
If the VH signal is output, replace VFD300 with new one.
3-1-3. Service hint (Any picture / Remark)
< Waveform of GR and SG signal >
Summary of Contents for CJ44
Page 17: ...2 2 ...
Page 19: ...2 6 2 5 ...
Page 21: ...2 8 A60 3 SPEAKER SECTION FRONT SPEAKER ...
Page 55: ...3 28 ...
Page 58: ...3 33 3 34 2 SMPS BLOCK DIAGRAM ...
Page 62: ...3 41 3 42 2 MAIN P C BOARD DIAGRAM TOP VIEW BOTTOM VIEW ...
Page 63: ...3 43 3 44 3 FRONT P C BOARD DIAGRAM TOP VIEW BOTTOM VIEW ...
Page 64: ...3 45 3 46 4 MIC P C BOARD DIAGRAM TOP VIEW BOTTOM VIEW ...
Page 65: ...3 47 3 48 ...