LG Flatron L1972H - No Raster Troubleshooting; No Raster;OSD (LIPS)

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Copyright
2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
LGE Internal Use Only
2. NO RASTER (OSD IS NOT DISPLAYED) – LIPS
CHECK IC501 INVERTER
ON/OFF PORT
J905 PIN9 5V?
NO RASTER
(OSD IS NOT DISPLAYED)
CHECK POWER BOARD
(LIPS)
CHECK J905
VOLTAGE PIN5,6
(5V)?
NO
NO
NO
NO
1. CONFIRM BRIGHTNESS
OSD CONTRL STATUS
2. CHECK SCALER DIM ADJ
PORT
3. CHECK SCALER LAMP
ADJ PORT
CHECK J905
PIN10
POWER BOARD (LIPS)
CHECK
PULSE AS
CONTACTING PROBE
TO THE LAMP
WIRE OF THE
LCD MODULE
REPLACE LCD MODULE
YES
1
3
2
4
YES
YES
YES
Waveforms
1
J905-#5,6
2
J905-#9
4
LAMP CURRENT
33
J905-#9 (Brightness 100) J905-#10 (Brightness 0)