Main Key Backlight Led Trouble Shooting - LG KM710 Service Manual

4.19 Main Key Backlight LED Trouble Shooting

z Keypad backlight LED Operation scheme is shown below.
VBAT
R703
10
LD700 C
SSC-SWTS1007
z Backlight operation
- Keypad backlight LED is controlled with LED_BC signal
- LED_BC signal from DBB(U103)
- The LEDs are forward biased and turned on
z Check Point
- VBAT level ( 3.35 ~4.2V)
- LEDs
- Main key, Main, Main FPCB connection
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Only for training and service purposes
R704
10
LD701
SSC-SWTS1007
LED_MAINKEY
- 95 -
4. Trouble Shooting
LGE Internal Use Only