2017 Mercedes Benz C 43 AMG Diagnostic and Repair# P-46_30-40A Date: 071127

Steering - Flow Noises/Fluid Foaming After Repairs
Date: November 27, 2007
Order No.: P-B-46.30/40a
Supersedes: P-B-46.30/40 dated April 26, 2006
Group: 46
Revision History
Revision Date Purpose
a 11/27/07 WIS Document Information Updated
- 4/26/06 Initial issue
SUBJECT:
All Passenger Models
Flow Noises from Area of Power Steering Pump and/or Foaming of Power Steering Oil in Reservoir
If you receive customer reports in the above model vehicles of flow noises from the area of the power steering pump, and/or foaming of the power
steering fluid in the reservoir following work carried out on the hydraulic steering system; this may be caused by an improper procedure followed for
filling and bleeding of the power steering fluid into the system.
To remedy, it is absolutely necessary to make sure that the procedure described in the WIS documents is strictly adhered to. In particular, it is
necessary to turn the steering to full lock-to-lock at least 30 times BEFORE STARTING THE ENGINE. If this is not done prior to starting engine,
there is a high risk of air entering the steering system, which is subsequently very difficult to eliminate.
Note:
Starting the engine prior to bleeding can cause irreparable damage to the power steering pump and will cause an air cushion to form in the
steering gear which causes noise. Once the air is ingested, the ingested air will only dissipate after driving the vehicle for at least 30 miles.
Mercedes Benz C 43 AMG (202.033) V8-4.3L (113.944) Page 318
Refer to the chart shown for the correct WIS document reference for the proper filling and bleeding procedure of the power steering pump.