LG FLATRON L1750S - Troubleshooting No Raster (LIPS)

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2. NO RASTER (OSD IS NOT DISPLAYED) – LIPS
CHECK MICOM INV
ON/OFF PORT.
(U501 PIN9)
J705 PIN9
2.5V?
NO
NO RASTER
(OSD IS NOT DISPLAYED)
CHECK LIPS
J705
PIN5, PIN 6
5V?
NO
1. CONFIRM BRIGHTNESS
OSD CONTRL STATE.
2. CHECK MICOM DIM-ADJ
PORT(U501 PIN41)
J705 PIN10
5V?
NO
LIPS
CHECK
PULSE AS
CONTACTING SCOPE
PROBE TO CAUTION LABEL.
(CONTACT PROBE TO
CAUTION LABEL.
CAN YOU SEE PULSE
AT YOUR
SCOPE?
NO
REPLACE CCFL LAMP
IN THE LCD MODULE
YES
YES
YES
YES
3 4
Waveforms
J705-#9 J705-#9
1
3 4
Inverter Off
Micom Port check
J705 Inverter output
Inverter On
Micom Port check
J705 Inverter output
1
J705-#5, 6 / U801-#1/U803-#3
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