Unlock additional heater

This function is used to unlock the additional heater/parking heater.
The heater may lock for any of the following reasons:
Test conditions:
Procedure:
  1. Select the "Unlock additional heater" function.
  2. Confirm with "OK" to unlock the heater.
  3. A dialogue box shows whether the operation has succeeded or failed. Confirm with "OK".
  4. Exit the function.
  5. Check that no trouble codes are stored in the heater.