LG KM710 Service Manual page 95

4. Trouble Shooting
z MAIN KEY Backlight LED Trouble
Is the Voltage level VBAT
LED700 ~701(Main key)
Backlight will work
LGE Internal Use Only
START
3.35 ~4.2?
YES
Are all LEDs
Working?
YES
Main key is
Working?
YES
properly
NO
Charge Battery
NO
Check the soldering of
R703, R704 or Replace
LEDs not working
NO
Check the condition of
doom sheet. If problem,
Replace the doom sheet
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