19" LCD Color Monitor COMPAQ W19Q
34
9.2 Trouble Shooting
9.2.1 Main Board
1
、
No power
Note: 1. If replace “MAIN-BOARD”, Please re-do “DDC-content” programmed & “WHITE-Balance”.
2. If replace “Power Board” only, Please re-do “ WHITE-Balance”
Measured CN601 pin5/6 = 12V?
Measured CN601 pin 9/10= 5V?
Measured U601 pin 2= 3.3V?
Measured U602 pin 2= 1.8V?
Check Correspondent component.
Is there any shortage or cold solder?
Yes. There is OSD show
Yes, all DC level exist
Disconnected the Signal cable (Loose the
Signal cable), Is the screen show “Cable Not
Connected”?
Connected the Signal cable again,
Check LED status.
Show noting
Connected the Signal cable
again Check LED status.
Check Power switch is in Power-on
status, and check if Power switch had
been stuck?
Led Orange
OK, Keyboard no stuck
Led orange
Led Green
Measured RGB (FB201, FB202, FB203)
H,V Input at U401 pin 89,90 ,was there
have signal ?
Check Correspondent
component short/open
(Protection Diode)
NG
OK, Wire tight enough
Check Panel-Power Circuit Block
OK, Panel Power OK
Check U401 Data-output Block
Replace Power board and Check
Inverter control relative circuit
Re-do White balance adjust
OK, input Normal
Measured Crystal X301 (14.318MHz)
OK, clock normal
Replace U401
OK
OK
Check the Wire-Harness from
CN402 was tight enough?
