LG-TM250
5. When Keytone isn't heard.
No
Yes
Check CON300
(Earjack)
EJACK_SENSE/ signal at #4
pin of CON300 is High?
Yes
Yes
Yes
NO
NO
NO
Yes
NO
Change Main B’d
Good
Between two
Earpiece
Change Earpiece
Soldering
Earpiece
Earpiece soldering
OK?
Resoldering peripheral
circuit of
Keytone wave
appear at 23,24pin
of CON404
Keytone heard
at hand set?
Supply
Power
to
START
LG Electronics Inc.
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