Samsung Galaxy Note 4 screen remains dark after phone call

If you make in a phone call with your Samsung Galaxy Note 4, it can happen that the display remains dark after terminating the call. It is not possible to make any actions until you have turned off the smartphone via the power button and turned it on again. Usually this error occurs after each call.

The reason of this error is the proximity sensor of the Samsung Galaxy Note 4. The Samsung Galaxy Note 4 uses this sensor during a call to check if your face is near the phone. So the display doens´t needs to be lit continously during the whole call. When the proximity sensor is covered or blocked then it may happen that the smartphone stays at the status "calling" although you already finished the call.

So now you have to check whether the proximity sensor of your Samsung Galaxy Note 4 is covered with something. The sensor is located right next to the earpiece. You have to check:

     - Have you stuck a screen protector? If so, does it covers the sensor?
     - Is dirt or dust in front of the sensor?

If the sensor is covered, then you need to make it clear.

If you do not find anything, check the values of the sensor via the service menu of your Samsung Galaxy Note 4. This works as follows:

Navigate in the service menu of your Samsung Galaxy Note 4 by opening the phone app and then entering the code *#0*# at the keypad. In the service menu, tap at the "Sensor" field. The second entry is called "Proximity Sensor" . The value of "ADC" should be about 10-15, so that the proximity sensor of your Samsung Galaxy Note 4 works properly. A values close to 50 indicates a problem with dust.

In "proximity" the value should be "0", since this means that the sensor has not been triggered. "1" means that the sensor is triggered and activates features that are associated with it in Android.

There are two possibilities:

     1. Dust has come under the glass of the proximity sensor
     2. The proximity sensor on your Samsung Galaxy Note 4 was installed not correctly --> warranty

If your note dust under the glass, then you can still try the following trick:

It may be that dust is permeated through the earpiece to the proximity sensor and therefore triggers this. Take a straw and blow with it into the earpiece towards the proximity sensor. As a result, the dust may moves away from the sensor and with a little luck the proximity sensor works properly again.