BenQ Q7T3 Series User manual

Q7T3(CPT panel) LCD Monitor Service Guide
Trouble Shooting
1
Q7T3-CPT TROUBLE SHOOTING GUIDE
1.No Display or display is unstable
Nopictureorpictureunstable
Poweroff Yes Turnonpower
No
Doescableplugsin No Checkallofwirethenturnonpower
connector? switchagain.
Yes
Doespowerstable? No CheckPowerBD
Yes
IsLEDlightgreen/orange? No CheckcontrolBD
Yes
Is LED status normal? No Check Flash Rom or replace it
Yes
Does crystal work correctly? No Check crystal CKT or replace it
Yes
Is interface BD normally? No Replace interface BD
Yes
Replace panel

Q7T3(CPT panel) LCD Monitor Service Guide
Trouble Shooting
2
2. BUTTON function:
OSDisnotworking
Yes
IscontrolBDconnecting? No PlugcontrolBDthenretry
Yes
Is bottom switch normally? Yes Replace control BD then retry
No
Replace Control BD
IsOSDworking??
No
Check Interface BD
3. OSD function:
OSD doesn’t work
Is control BD working? No Replace control BD
Check interface BD

Q7T3(CPT panel) LCD Monitor Service Guide
Trouble Shooting
3
4. Power Board
Backlight didn't shine
LED shined?
3.3V existed? IS I/F board connected?
IC751 PIN 9 IS 15V?Replace Q761
PWM existed?
(BLT_ADJ)
Plug CN701 again or
checking I/F BD
Turn on level existed?
(BLT_ON)
Insert them again Check CN752, CN753
was pluged properly?
Plug CN601 again or
checking PW BD
Replace IC751,Q751
Replace new fuse
Replace new fuse
Check IC701 OK?
Checking F601
Broke?
Check IC601 Vcc
existed?
Replace IC602,
IC702,D702 or check
I/F BD
Replace IC701
Replace new fuse
Replace
IC601,ZD601,C606,
C611
Y
N
N
N
N
Y
Y
Y
Y
N
Y
YN
N
Y
Y
Y
N
N
N