LG L240 Service Manual page 83

4. TROUBLE SHOOTING
z KEY Backlight LED Trouble
Is the Voltage level VBAT
Are all LEDs LD501 ~514
Backlight will work properly
START
3.35 ~4.2?
YES
Working?
YES
Q501 is
Working?
YES
- 84 -
NO
Charge Battery
NO
Check the soldering of each
R or Replace LESs not
working
NO
Check the condition of
Q501
If problem, Replace Q501