The Samsung Galaxy S9 has a built-in compass, which is provided by means of a built-in magnetic sensor. In addition to the Edge toolbar, there are several apps that you can download from the Google Play Store to access the compass functions.
If you notice that the compass does not work properly and displays incorrect cardinal points, you can calibrate the compass or magnet sensor as follows:
Calibrate the Samsung Galaxy S9 compass:
1. When you are on the initial screen, open the phone app
2. Select the dialing keypad to enter numbers manually.
3. Next, enter *#0*# on your Samsung Galaxy S9 or S9 Plus smartphone.
4. The service menu opens. Select "Sensor" and scroll down to the bottom of the next menu.
You will now see "Magnetic Sensor" and below it a circle with a line and a number behind it. This has the following meaning:
- Red line with a 0 = The compass sensor must be calibrated
- Blue line with a 3 = The magnetic sensor is calibrated
In order to calibrate the compass, the Samsung Galaxy S9 rotates once around all its three axes. Do this until the circle shows a blue line and a 3. Only then is your compass calibrated.