Checking level sensor

This function is used to check the level sensor function when the vehicle height is changed.
Raise and lower the axles, read the level sensor values and check that they change.
Test conditions:
Procedure:
  1. Start the function.
  2. Choose the axle to be raised or lowered.
  3. Check that the different values are changed.
  4. Check that right and left sensors give approx. the same value.
  5. Repeat the test for the other axles.
  6. The function is done.