Pressure regulation
â–¶ How to fix
Check the solenoid valves using the diagnostics program. Check the compressed air pipes between the APS and compressor. Check the compressor. Renew defective components. Erase the fault code.
What you'll see
No driver-visible symptom recorded.
System reaction
No system-reaction text recorded.
Diagnostic depth
Detection
The air pressure does not fall when the control unit starts regeneration.
Possible cause
Electrical or mechanical fault in the control unit, compressor or solenoid valve. The fault may also be caused by freezing in the drain valve, a blocked silencer or leaks in the pneumatic signal pipe between the APS and compressor.