LG KE520 Service Manual page 77

4. TROUBLE SHOOTING
Power is supplied to
Connection between
FPCB and boards is OK?
Connectors are soldered well?
Paths of LCD control
signals are OK?
After changing the board,
LCD Display is OK?
Change the board
LGE Internal Use Only
START
the board?
Yes
First of all, push a key pad then check 1.8/2.8V
check Points during a Key pad LED ON.
Yes
Yes
Yes You must push a key pad for a watching signals.
FPCB OK?
Yes
Yes
- 78 -
Refer to
No
Power On Trouble
No
Reconnect FPCB
No
Re-solder the
Connector
No
Re-solder
the EMI filter
No
Replace the FPCB
No
The LCD is broken.
Change the LCD.
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