Leakage check

Larger leaks can be found using the following procedure. Smaller leaks are considerably more difficult to find if the effects of temperature change and axle strain are to be ruled out. Specifications stipulate that the leak may equal up to 2 mm per day (constant temperature, vehicle standing on skid pads -> no axle strain).

• Position the vehicle in a room with largely constant temperature (± 3°C) for approx. 10 -12 h and adjust to the normal level. Do NOT set the parking brake!
• If the vehicle ride-level height deviates from the nominal ride-level height by more than ± 10 mm, adjust the vehicle to the nominal level again (ignition on, door open - --> all doors closed, adjust level, ignition off; let the engine run in emergencies only and only for a very brief time. Do not get into the vehicle.)
• Place the EHC control unit into production mode via the diagnosis and information system (deactivated level controller)
• Measure and note down the ride heights
• Leave the vehicle standing for another 10 -12 h (constant temperature, do not move the vehicle, do not get in or out or make any other load changes)
• Measure and note down the ride heights
• If the ride heights are lower than the initial measurement by more than 10 mm at one or more wheel stations, it can be concluded that there is a leak. Leaks may occur at the air lines, the pneumatic connecting elements and the spring strut.
• After completion of the leakage test, deactivate production mode again.