Calibration of rain sensor

This function is used to adapt the rain sensor to the windshield.
Note:
A calibration of the rain sensor must be performed:
Test conditions:
Procedure:
  1. Start the function.
  2. Check test conditions.
  3. Press "OK" to proceed.
  4. The calibration starts automatically.
  5. Function done.
  6. Activate the rain sensor and spray some water on the windshield to verify that the sensor is working.