LG G5500 Manual page 63

4.8.2. Speaker Trouble
START
Does sine wave appear
at C306, C307?
Yes
Connection between
receiver and board
is OK?
Yes
Soldering of SPK
is OK?
Yes
Speaker OK
Enter into Engineering Mode and
go to menu "Baseband → Alert
No
SPK_EN signal is high?
Yes
No
Reconnect
receiver
V_SRAM & V_IO
is 2.8V?
Yes
Melody IC is out of order.
Change the U301.
No
Resolder
the SPK
-64-
→
Ring"
No
Resolder the U303
otherwise Change it.
No Resolder the U301
otherwise Change it.