Implausible value
Carry out a leak test on the vehicle's compressed air system.Connect workshop air and check whether there is a leakage at the drain valve silencer or at the supply line. Possible causes of leaks at the silencer are faults on the regeneration circuit check valve or the drain valve. If there are air leaks underneath the circuit protection valve, the check valve should be checked. Otherwise the drain valve should be checked.Check that the compressor is functioning normally.Disconnect signal cable 4 at APS. Check that there is no air pressure from the compressor. Check whether the vehicle has been used in such a way that an extremely high air consumption or low air supply has occurred.If the air suspension is not behaving normally, carry out spare parts programming of the system. Check the bodywork for leaks in all operating positions. On vehicles built before the chassis number limits and dates below, spare parts programming can also be carried out. Södertälje: Chassis number: 2006964 Date: 2005-02-11Angers: Chassis number: 9097481 Date: 2005-01-29Zwolle: Chassis number: 5118031 Date: 2005-02-02
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
The air pressure never reaches the desired level. APS is never able to regenerate.
The air pressure has not reached 9 bar despite charging for a long time. This may have been caused by the following: The vehicle has been used in such as way that an extremely high air consumption and/or low air supply has occurred. An example of this is when vehicle functions with a high air consumption have been used for a long time or the vehicle has been driven at a low engine speed.Leaks in the drain valve, block circuit coupling or check valve on APS. Leaks in the compressor cylinder head, trailer connection or in the bodywork.Leaks from compressor signal cable to port 4.For some reason the air suspension is not behaving correctly and is consuming more air than necessary.A brake chamber diaphragm has broken on the vehicle or on the associated trailer.