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 DIG302 on FRONT board.
3-1-2. How to troubleshoot (Countermeasure)
1) Check if VKK, FL+ and FL- are output from SMPS to VFD via the MAIN board.
2) Check if IC501 outputs VFD_D0, VFD_CLK and VFD_STB to the FRONT board.
3) Check the GR signal(pulse signal) of IC408 on the FRONT board.
Check the SG signal(pulse signal) of IC408 on the FRONT board.
If the GR and SG signal isn’t output, replace IC408 with a new one.
If the GR and SG signal is output, replace DIG302 with a new one.
3-1-3. Service hint (Any picture / Remark)
GR signal
SG signal
< Waveform of GR and SG signal >
GR SIGNAL
ABOUT 30 V
SG SIGNAL
ABOUT 30 V
Click the picture,
and then drag to enlarge it.
Check the waveform on details.
Содержание CM4550
Страница 13: ...2 2 ...
Страница 17: ...A60 4 SPEAKER SECTION 4 1 FRONT SPEAKER CMS4550F ...
Страница 18: ...2 9 A90 4 2 SUBWOOFER SPEAKER CMS4550W ...
Страница 19: ...2 10 ...
Страница 50: ...4 USB 13 USB_5 V D D 14 3 31 IC501 PIN A8 IC501 PIN A7 ...
Страница 51: ...3 32 ...
Страница 66: ...3 61 3 62 2 MAIN P C BOARD TOP VIEW BOTTOM VIEW ...
Страница 67: ...3 63 3 64 3 FRONT P C BOARD TOP VIEW BOTTOM VIEW ...