Keypad Back Light Trouble - LG KC550 Service Manual

6. Trouble shooting

6.10 Keypad back light trouble

Check Points
- Signal path is connected well
- Analog SW is working properly
KP_IN(5:6)
KP_OUT(0:4)
B4
VOUT
D2
LED1
C2
LED2
C1
LED3
B1
LED4
B2
LED5
A2
LEDFL
F5
SBIAS
F3
SSENS
E4
GC1
E3
GC2
LGE Internal Use Only
R106
END_KEY
DOWN
KP_IN(5)
KP_IN(6)
KP_OUT(0)
KP_OUT(1)
KP_OUT(2)
KP_OUT(3)
KP_OUT(4)
MLED
MLED
MLED1
TP4
MLED2
R101
MLED3
MLED4
R108
MLED5
SUB_KEY_BL
R102
R107
Key Matrix and LEDs on KEY PCB
- 100 -
END
VBAT
END
150
CLEAR MENU SELECT
SEND LEFT RIGHT
SSC-TWH104-HL
LD101
10 SSC-TWH104-HL
LD106
10 SSC-TWH104-HL
LD102
10 SSC-TWH104-HL
LD105
10
Copyright © 2008 LG Electronics. Inc. All right reserved.
OK
UP
TP1
SUB_KEY_BL
Only for training and service purposes