User's Manual

1. Check if the microphone and lead is well ,and soldering is well ;
2. Check whether the relevant components have soldering problems or not;
3. Replace with new microphone, and verify again;
4. Enter the call state (or engineering test mode),measuring if microphone’s bias voltage is normal:
the voltage is when the microphone works about 1.8V, and 0V when off;
5. If you still have not found the problem, then check whether the U1 chip has soldering
or performance problems or not.
5.5. Receiver function abnormity
Rep
air steps:
1. Check if the receiver shrapnel’s elasticity is well, and contact with PCB well;
2. Check if the relevant components have soldering problems;
3. Replace with new receiver, and verify again;
4. If you still have not found the problem, then check whether the U1 chip has soldering
or performance problems or not.
5.6. Speaker function abnormity
Repair steps: