Roadstar DVR-9100, Руководство по обслуживанию, Страница: 7 / 76

5
TROUBLE SHOOTING
B. Power LED or VFD panel error
Front board LED
broken or contrary
polar ?
No LED display
Change LED
Change
VFD panel
VFD panel broken
or pin shot ?
12 pins cable between
front board and main
board is connected well.
F/B IC U1
#27 is –27v? #17,38 is 5v?
#40 is low voltage?
Are there signals
outputting form IC U1
#15~26,28,29
on F/B?
Are there singles
outputting form IC U34
#195~197
on M/B?
OK
Are there signals
inputting to IC U1
#5,6,8,9
on F/B?
Change F/B IC U1
Change M/B IC U25
else change M/B
Yes
No
No
Yes
No
Yes
No
Yes
No
Yes
No
Yes