noting that the proximity sensor is that little dot just above the speaker on the face of the phone. If after these two fixes, the sensor still isn't working properly, check for any software ...

[mircemk] shows how to create a simple non-contact proximity sensor using little more than an Arduino Nano board, and a convenient software library intended to measure the value of capacitors.

[mircemk] shows how to create a simple non-contact proximity sensor using little more than an Arduino Nano board, and a convenient software library intended to measure the value of capacitors.