Is the wiring insulation cracking? You may have an intermittent short on the wires going to the rack sensor. I know mine is cracking, reminds me of the smg gps harnesses ugh...

 

the car starts right up no problem runs fine and drives fine only thing is I lose power steering when I drive it with a Servtronic malfunction. I can start the car and let it sit running with it completely still and it will just randomly throw a Servtronic malfunction code and no one has touch the car or turned the wheel. It’s extremely weird. I also checked for voltage fluctuations when the malfunction occurs the voltage does not fluctuate at all.

 

There's no active steering module on the m5.

 

Hmm, this would indicate replacing the sensor may not solve the issue. The search now is to find out if the system power interrupts the sensor operation to isolate the issue at the sensor or the steering rack.

 

There is a sensor near the steering shaft on the rack that I believed was the problem from the research I did. So that being said I ordered a used sensor that was tested and in guaranteed good working condition. That’s 2 sensors that where in the car and it’s doing the same exact thing, random (servtronic malfunction) that happens often. There is only one sensor on the rack and pinion right?

 

yes means no other sensor other than what we are talking about.

 

So earlier I went into all control modules and read the fault memory here’s what I received.

 

After I documented all the codes that were in there i cleared them and I’ve had the car running for about two hours now and drove it for about 45 minutes to an hour. I then scanned it again with INPA and these are the trouble codes I received. I have not received a Servtronic malfunction in the I drive control message sense I cleared the codes. For the 520a code I tried to re set the steering angle and I can not access the active steering under chassis or body. I also get an error message.

 

OK we lost the evidence by deleting, wait until it comes up again.
Delete this INPA and download INPA (BMW Standard Tool) it comes with an installer from bimmergeek.com, this one is missing some files. You should access the KGM but missing its file.ipo. You need to access to see the details of the fault and diagnose better.

 

Ok thank you for your help. When I get home I will go on Beamer geeks and download the newest version.

 

Yeah do that. I think the KGM has a history memory so we can retrieve the fault detail from there once you access it unless you deleted the history memory too.

 

How does the rack and pinion interact with the steering angle sensor optical disc behind the steering wheel? Does turning the wheel produce an expected number of degrees turn that needs to move the rack a certain number of teeth?

 

Reason I ask is that maybe the implausibility signal is tied to that feedback loop?

 

No it doesn't reflect the mechanical turn angle. The steering angel sensor measure the steering wheel rotation degree of 440 to the right and 440 to the left which equal to 2 turn and 1/3 from lock to lock, the wheel and tire turn 45 degree approximately in response.

I don't think the system uses the steering angle sensor to test plausibility in term of servotronic, this evaluation check doesn't exist simply because there is no fault code for it. The code in this case is hardware failure and this can be caused by electrical or power issue or failed control unit internal circuitry (KGM). In addition, there is no feed back signal from the steering hydraulic flow, servo sensor or the steering mechanical angle, the steering angle sensor signal doesn't reflect the actual mechanical turn angle. The car system (DSC) will accept steering wheel deviation during the calibration process up to certain degree. In other word, if you disconnect the steering shaft from the rack input shaft and turned the steering wheel and tried to calibrate the steering sensor the system will take it.

 

So I believe the car is all set with the steering issues last Wednesday I cleared all the codes and reset steering to 0°. have been driving it since last Wednesday I put about 350 miles on it no steering issues. I appreciate all your help I believe in my scenario I just needed to readapted servtronic sensor. Knock on wood I will let you know if anything changes.
Ps. I recently noticed some rough idle coltstart issues I will be starting a thread on if you guys care to chime in. thank you again.

 

Totally reasonable - I was just wondering aloud when I saw this thread if there was any interplay between the steering wheel sensor disc and the rack - never had a reason to look into it myself!

 

Interesting if it's related, what was the steering sensor reading before the reset?. I am sure the servotronic is a speed dependent but all is possible since it was hard fault and no more fault now.

When I purchased my car the steering angle sensor was all over the place with 3 faults and DSC related fault and never trigger the servotronic, sorry but hope it is fix for you.

 

Hi there I have same exact issue with e64 so any one have clue what is the problem any one solved?,,?

 

As per the OP the fix is to do the steering angle sensor adjustment. Try and report back here.

 

Hi so I did the steering angle adjustment and it's partially work so some time work properly and some time no I don't know what to do

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Explain your symptoms, show fault codes, what is that doesn't work and?. Show picture, print screen, etc...