Trouble Shooting Guide - BenQ M2700HD Service Manual

5.7 Trouble Shooting Guide

Inverter trouble shooting
Backlight can't be turned on
No raster?
LED Green?
Backlight can't be
Is there 5Vdc voltage
on pin2 of IC501?
Is there high-level voltage on
pin6 of IC501?
Are connected rightly
CN501, CN502, CN503
Is there instantaneously pulse
wave on pin1, pin16 of IC501
at the moment of restart?
Is ok T501, T502?
Check feedback circuit
ISEN1,ISEN2,VSEN,OLP1,OLP2
Yes
Yes
Yes
No
Yes
Yes
Yes
Yes
No
Yes
Check power
supply
No
Is Ok R505?
No
No
No
Is Ok IC501?
47
Yes
Check I/F board
R505 open
Connecting the
output connector
Yes
U501, U502 fail
No
IC501 fail
T501, T502 fail
END