Buffalo BU1715, Service Manual

Page: 42 / 58

Buffalo BU1715
42
2.) W / LED, No Backlight
Change Q201 or Q202
Check C201 (+) =12V
NG
OK
Check D201/Q209/Q210
Check ON/OFF signal
Check Interface board
NG
OK
Check U201 pin9=12V voltage of C905(+)
NG
OK
Check the pin1 of U201 have saw tooth wave
NG
OK
Change U201
Check D201 (-), D202 (-) has the output of square wave at short time.
NG
OK
Check Q205/Q207/Q203/D201
or Q206/Q208/Q204/D202
Check the resonant wave of pin2 & pin5 for PT201/PT202
NG
Check the output of PT201/PT202
Check Q209/Q210/C213 or
Q211/Q212/C214
Check connecter & lamp
OK
NG
Change PT201 or PT202
OK