LG SPM2 - Led Doesnt Work

3-13
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Only for training and service purposes.
ONE POINT REPAIR GUIDE
4. LED DOESN’T WORK
When you turn on your set, Boots up and works, but the LED does not work.
4-1. Check LED power (LED_PWR) and I2C, LED_SDB
4-1-1. Solution
Replace MAIN board.
4-1-2. How to troubleshoot (Countermeasure)
1) Please check status of LED cable connection. (at CN101 and LED Board)
2) Please check LED_PWR (5 V).
a) If LED_PWR is abnormal, replace MAIN board.
b) If LED_PWR is OK, replace LED board.
3) Please check I2C(point 2, 3), LED_SDB(point 4).
a) If I2C is abnormal, replace MAIN board.
b) If LED_SDB is Low, replace MAIN board.
c) If I2C and LED_SDB is OK, replace FRONT board.
4-1-3. Service hint (Any picture / Remark)
<=> LED
SDB
SDA
SCL
GND
GND
5V0
5V0
CWBSP2CN101
FROM MCL3730SD - LED
C110
50V/33pF
C111
50V/33pF
C112
50V/33pF
C102
10V/0.1uF
C103
16V/1uF
C104
10V/10uF
1
2
3
4
5
6
7
CN101
C105
10V/0.1uF
L101
220ohm/2200mA
L102
CB05YTYH221
L126
600ohm/0.5A
L127
600ohm/0.5A
L128
600ohm/0.5A
DGND
LED_PWR
DGND
LED_SDB
LED_SCL
LED_SDA








< MAIN board top view >
CN101
CN101







