LG F1200 Service Manual page 49

4. TROUBLE SHOOTING
(6) Earphone Trouble
START
lnsert Earphone to
the phone
Does the audio
profile of the phone change to
the earphone mode?
YES
Set audio part of the
test equipment to
echo mode
Can you hear your voice from
the earphone?
YES
Earphone will work
properly
Earphone Detection Problem
Check voltage at
R507.
Is it about 0V?
YES
Change the Main-PCB
NO
NO
Start
NO
YES
Go to
Earphone Detection Problem
Set audio part of the
test equipment to
CW mode
Can you hear CW
sound?
YES
Go to
Earphone Sending Problem
Check the Soldering
status R507, CN500
Replace the
Remote controller
- 48 -
NO
Go to
Earphone Receiving problem
NO
Resolder
R507, CN500