LG G5500 Manual page 62

4.8.1. Receiver Trouble
Does sine wave appear
SPK_EN signal is low?
cable and board is OK?
Twist pair cable of receiver
START
at R308, R309?
Yes
Yes
Connection between
Yes
Is OK?
Yes
No Trouble
Set audio part at test equipment as PRBS
or continuous wave, not echo. Set the
audio volume max.
No
ABB is out of order.
Change the board.
No
Resolder the U303.
Otherwise change it.
No
Reconnect the cable
No
Change the receiver
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