Air Suspension - Thumping Noised From Front/Rear Axle

Thumping noises on rough roads from area of front and/or rear axle.

Topic number LI32.22-P-053867

Version 1

Design group 32.22 Air suspension

Date 05-22-2012

Validity MODEL 166 with AIRMATIC (SA code 489) without
MODEL 166.074 (AMG vehicles)

Reason for change

Complaint:
Thumping noises on rough roads from the area of the front and/or rear axle in the vehicle speed range up to 12 mph / 20 km/h.

Cause:
Pressure pulsations on switching of the ADS damping modules can cause thumping noises if the tolerances of the components are unfavorable

Remedy:
Perform Xentry update:

For Xentry Diagnostics DVD 5/2012 use add-on 2306.

For Xentry Diagnostics DVD 3/2012 use add-on 2285.

Then use control unit programming to flash the software A166 902 5602 into the AIRMATIC control unit.

If the software update does not bring the desired result, the cause of the problem is elsewhere. In this case locate the source of the noise using the Chassis Ear.





Symptoms





Work units