Sony Xperia TX LT29i Working Instructions page 103

Problem Areas: Microphone
3. If the two BtB connectors or the FPC of Key Flex FPC is
damaged – replace the Key Flex FPC.
Check:
Inspect the microphone on the Sub Board Assy.
Action:
1. If dirty – clean it.
2. If the microphone or the BtB connector of the Sub Board
Assy is damaged – replace the Sub Board Assy.
3. Replace board.
1266-5087 Rev 1
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Sony Mobile Communications AB – Company Internal
Troubleshooting Guide (mech)
21(57)