LG KU250 Service Manual - Page 106
Receiver Path
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4. TROUBLE SHOOTING 4.16 Receiver Path MSM6245 EAR1ON/EAR1OP → R421,R422 → Analog Switch(U401) → Receiver Start Connect the phone to network Equipment and setup call Setup 1KHz tone out Can you hear the tone? NO The sine wave appears at L401, L402? NO The sine wave appears at R421, R422? NO Change the Main board YES END YES Change receiver YES Check the analog switch - 107 -
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4. TROUBLE SHOOTING
- 107 -
4.16 Receiver Path
MSM6245 EAR1ON/EAR1OP
→
R421,R422
→
Analog Switch(U401)
→
Receiver
Start
Connect the phone to network
Equipment and setup call
Setup 1KHz tone out
NO
The sine wave appears at
L401, L402?
YES
NO
Can you hear the tone?
Change receiver
YES
END
Change the Main board
The sine wave appears at
R421, R422?
Check the analog switch
YES
NO