Motorola Moto X Pure Edition Troubleshooting Manuals page 60

Tertiary Microphone
If the Tertiary MIC is not functioning ...
- Check MIC bias at C4520 or C4524 or C4523. This should be 1.7~1.8V when the microphone is
enabled.
- Check the 3 rd microphone sealing grommet and adhesive on the 3
adhesive have been assembled abnormally, the MIC hole could be blocked while it has been
assembled. (See image below)
- Check the microphone output at C4521 or C4522. The AC amplitude should increase (Output DC bias
should be around 0.7V), when audio is present.
MOTOROLA CONFIDENTIAL
rd MIC part. If the grommet and
Blocked hole
Baseband TROUBLESHOOTING GUIDES
Moto X Pure Edition/Moto X Style