LG T5100 Service Manual page 58

Keypad Backlight Trouble (Case of all LEDs are not working)
START
Enter into Engineering Mode
The Voltage of LED signal
is abou t 0V?
Yes Power off and Measure the
Resistor Value of all LEDs.
Is the re anything that
resistor value across LED
No
Keypad Display is OK.
Keypad Backlight Trouble (Case of any LED is not working)
START
The path is OK?
Yes
The LED is out of order.
Change the LED.
and select Keypad On
No
ABB is out of
order.
Yes
Replace the LED.
It is out of order.
Enter into Engineering Mode
and select Keypad On
No
Resolder the path
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