
47
5.7 Trouble Shooting Guide
Inverter trouble shooting
Backlight can’t be turned on
Is Ok R505?
Yes
Yes
No
Check power
supply
Is there 5Vdc voltage
on pin2 of IC501?
No raster?
Yes
Yes
LED Green?
Backlight can’t be
Yes
Is there high-level voltage on
pin6 of IC501?
No
No
Yes
Check I/F board
R505 open
No
Connecting the
output connector
Yes
Are connected rightly
CN501, CN502, CN503
Yes
No
U501, U502 fail
IC501 fail
No
Is Ok IC501?
Is there instantaneously pulse
wave on pin1, pin16 of IC501
at the moment of restart?
Yes
No
Yes
Check feedback circuit
ISEN1,ISEN2,VSEN,OLP1,OLP2
END
T501, T502 fail
Is ok T501, T502?
Summary of Contents for M2700HD
Page 23: ...BenQ M2700HD Service Manual 22 13 Assemble the hinge cover ...
Page 28: ...BenQ M2700HD Service Manual 27 14 Remove the panel ...
Page 29: ...28 5 Circuit Board and Standard Parts Replacement 5 1 Block diagram Power Board ...
Page 30: ...29 ...
Page 31: ...30 ...
Page 32: ...31 ...
Page 33: ...32 IF Board ...
Page 34: ...33 ...
Page 35: ...34 ...
Page 36: ...35 ...
Page 37: ...36 ...
Page 38: ...37 ...
Page 39: ...38 ...
Page 40: ...39 ...
Page 41: ...40 ...
Page 42: ...41 ...
Page 43: ...42 Keypad ...
Page 44: ...43 IF board layout Keypad board layout PI board layout ...