asolomu

Hello, I own a Mercedes ML350 4matic (W164) and recently it developed an issue with the steering angle sensor. Thus I get the following message on the dashboard: ESP malfunction..
I have an iCarsoft M900 V2 scanning tool and when I plug it I get the error: Component N49 (Steering angle sensor) is defective. However, when I check the readings of the sensor, I see that the sensor tracks correctly the steering angle as well as the steering wheel "turns".
The only weird reading I get is that the "abrupt change in steering wheel" is always on the "Yes" state. However, I dont understand what exactly does that mean.

I understand that something is not working properly, but since the sensor is reading correctly the information regarding the steering wheel angle, I dont understand why it is considered as defective.
I will appreciate any ideas on how I will be able to debug the problem.

Maj. Dundee

Please UPDATE YOUR PROFILE in USER CP to include the year of your ML 350 Gas or diesel and where you live.

Maj. Dundee

What code # are you getting in the ESP module?

Is the plastic cover on the steering column loose?

Re-initialize the Steer. Angle Sensor; start eng. with steering wheel centered. Turn the wheel all the way to one side and then to the other and recenter the wheel.

Then clear the code.

asolomu

These are all the codes that I am getting. I suppose that the number that I see on the top of the Icarsoft screen for each message is the fault code.
In the ESP module I get two messages:
1) 9035 [No CAN data “Steering angle” from control module N80 (Steering Column) ] or [Ignore fault code with theis control module variant]
2) 9039 [No CAN data ‘’Yaw rate’ from control module N47-5 (ESP control module)] or [Ignore fault code with this control module variant]
In the steering column module I get one message:
1) 9334 Component N94 (steering angle sensor) is defective

The plastic cover is indeed loose.
I have tried what you have suggested but the error comes back once I clear it (after performing the steering angle initialization).
I am attaching pictures from the readings of the steering angle sensor in case they will be helpful.
Any ideas?

Maj. Dundee

On the right hand side of the steering column you will see an access hole.

Center the cover and with an extended T27 torx bit tighten the screw. Tighten it but do not over do it.

Then reinitialize and then clear the code.

If after tightening, etc., the code does not erase, you will need a new SA sensor.

asolomu

ok, let me try and I will let you know the results. Thanks for the help.

asolomu

I just tighten the screw and now the cover is not moving. I cleared all the codes and re-initialized the steering angle sensor, however, the error came up again as soon as I turned the steering wheel.

I believe that I have to replace the sensor as you have suggested.

However, it is still weird, why the sensor appears to work properly based on its readings (at least based on my interpretations) while is considered at faulty state. All the readings seem to be normal and if I plot the wave of the sensor while turning the wheel, everything seems to be nice and smooth. The only problem is that the sensors state is “Fasle”. Is there anything else that I can check in order to understand why the sensor is considered defective?

Maj. Dundee

What code/s? If they are the same codes as before, you should say so.

asolomu

Sorry about that Yes the codes are exactly the same.

By the way, I also noticed that once I turn on the car the steerijg angle sensor is on state "yes". Once I move the steering wheel instantly it changes to "False".

Maj. Dundee

Well, code 9334 says the the SAS is defective. Make a decision.

asolomu

Hehe, yes I know. Thanks for your time and help!

Antonio s600

Having the same issue now. What was your solution to your problem?

asolomu

In my case the solution was to replace the sensor. If you havent already, I would suggest to try to re-calibrate the sensor first (turning the wheel end to end a few times). If that doesnt work, you may need to replace it.

Antonio s600

I have done every turn from left to right thing I've seen and read about that's on line. My biggest mystery is my steering wheel is aligned and even. When I took it to a shop ( not a Mercedes shop) they said my steering angle is showing the proper degree angles when they hook it up to the diag. They said the steering angle sensor is fully functioning correctly.

asolomu

If that helps. My steering angle sensor also seamed to read well the steering angle. However the error was there and no matter what I tried ( re-calibrating, deleting errors using obd reader, reconnecting cables etc) was coming back.
I fixed it only when I replaced the sensor...

Antonio s600

Did you replace it your self? If so, was if difficult?

asolomu

A local shop replaced the sensor. It didnt look difficult.., but I didnt try it myself.

Antonio s600

Ok. Also....thanks for the feed back. I really appreciate it.

leoleoleo

what sensor of the rack ?