I had a bit of an odd thing with my old 58 plate 520d

It has had an error code for a while saying “start assist inactive” – but I hadn’t had any actual issues when driving so I decided to just live with it – as BMW seem to want 300 quid to even look at any of the codes.

When I did a bit or googling I read that this could be an issue with the steering angle sensor - and I did notice that the steering wheel was a fraction offset to the right in the straight ahead position so this makes sense.

Now I have just had to replace a track rod end – which was fine (although seized as usual) set it up by eye - and then took it for tracking at a local Kwik-fit with a 4 wheel rig.

They have set it up accurately according to toe settings but the steering wheel is a fraction offset the other way now.

Now when driving the DSC light ( yellow triangle with a clockwise arrow around it ) lights up on the dash after a few minutes driving in a straight line.

My guess is the DSC system doesn’t like the fact that there is a tiny amount of left hand lock on – even though it seemed happy to have a greater amount of right hand lock on - for the past year or

So - given that it worked fine before without DSC lights – and given that I don’t really want to spend 1000’s on the old barge to replace steering sensor and code it to the car - what are my options ??

Take it back to Kwik fit and have them adjust so the steering wheel is back where it was?

How much of a job and cost is a steering sensor ?

 

They didn't perform the alignment correctly and that's the reason you have the DSC light. Personally I would replace the sensor with a used one (I've done it twice on mine). It's an easy DIY. The only thing is afterwards timing needs to be reset. If you have BMW software tools and a cable it only takes a couple of mins to do. I always take my car to a BMW Indy or dealership for alignment because they are the only ones that know how to do it correctly.

 

HI Sean
thanks for that

good to know the sensor is an easy DIY job - i did buy the cables and software some time ago when i was doing the lights module - but the one i got just kinda worked so have never used them - the software install process seemed to be a pfaff - will have a look for a used one

do you think its simply the alignment was set wrong - a local independent who usually works on my car recommended the local Kwikfit as they didn't have 4 wheel alignment rig - and said Kwikfit were the only localish place with one - and they send all theirs there

i can take it back and get them to set it so the wheel is dead ahead in a straight line but a bit concerned it will still throw the DSC code up - as i read the car sets teh steering wheel at a slight right hand angle when it senses the steering sensor is falty as a kind of tel tale - so i wondered if it will still throw a code if the TRE's are set to dead ahead when the steering angle is perfectly centred - as the ECU / DSC is expeting the wheel to be slightly to the right when dead ahead with a duff sensor

it may be safer to have them set it back to how it was 10 degrees of right hand lock when wheels are dead ahead

any thoughts ?

 

A faulty SZL will cause a DSC light. When mine went bad both times my steering wheel stayed straight but I have a 05 pre-LCI. Correct the SZL first and see what you get. You'll need to calibrate the steering so hopefully everything corrects itself afterwards. How does it drive. Does it feel like the car is skating? If not do not worry about the alignment right now. Fix the SZL as that will give you your initial DSC code.

 

hi Sean

car has driven fine for the last year without the DSC light on - but with the steering wheel at a slight angle ( around 10 degrees ) to the right when going dead ahead - only error message was "start assistant inactive" on the infotainment screen on start up - which i read was likely to do with the steering angle sensor - it may be throwing a code also - but have not connected a laptop to see - only the warning message in the info screen - definitely no DSC light.illuminated on the dash
the car also drove absolutely fine - at no point did it feel like any brakes or traction control were being applied by the DSC

since having the tracking set - the steering wheel is slightly turned to the left ( but only a little maybe 5 degrees off centre ) - but since i came out of the tyre place the DSC light comes on after 1-2 mins driving in a straight line.
car still drives normally - no sign of DSC actually doing anything -

i have it booked back in at the tyre place - as the steering wheel is off centre which is not right - and i wonder if the issue goes away if its set straight -
But maybe it needs to be back to 10 degrees to the right as it was before for the system to be happy ??

will ned to get a new / replacement sensor and have a go at fixing it properly at some point

 

OK - quick update

took it back to the Kwikfit - had them look at it again - spoke to the guy that did it - he said the guy that had done it the first time had it set way out - ( even though i saw the readouts on the screen at the time that said it was fine ) - anyway no DSC lights on the way back
tried a 1/2 mile stretch of totally straight dual carriageway - and it was fine

seems to be solved

may do the steering sensor at some point its its not a big job

thanks for your help

 

If you put your scanner on and monitor the SAS, you should be able to see 0° when you wheel is straight. Go full lock to the right, then to the left and observe the ° when the wheel is in full lock. If they are within 3 digits of each other and doesn't skip digits in its travel, there is no need to replace it.
Some SAS unit only allow +/- 2 degrees of tolerance before it triggers a code and I've seen others that allow +/- 4 degrees.

 

good input - much appreciated - will try that when i finally get around to installing the INSTA package - which has been putting me off as it looks like a right PITA!