LG H990ds Service Manual page 75

3.14 Display
When Main display is does not working check CN7501 and TP Voltage.
Checking Flow
START
Power On SW
Power is ON?
Yes
Yes
Main FPCB Connector(CN2)
Connected?
No
LCD Display OK?
No
TP1: +5.5V, TP2: -5.5V,
TP3: 1.8V, TP4 : 3.3V
Yes
Replace
LCD Module
LCD Display OK?
Yes
END
LGE Internal Use Only
No
Power Guide
No
No
Replace
Main PCB
BOTTOM
TP2
CN2
TP3
75
3. TROUBLE SHOOTING
Image
TP1
TP4
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