DSC & ABS Falure - E46
Discussion
Advice please chaps ....51 plate 330d.
After a few minutes driving, I get 3 lights up. H/brake, Traction & ABS. As you might expect when this occurs I lose all ABS / TC / DSC etc. (great this week!!!)
(This has been happening for a couple of weeks now so its not particularly weather related)
Local indy reckons it's the ECU .. estimated at £1500?
so a number of questions really but in essence...
1) How likely does that sound
2) any work around ideas?
Help really appreciated - I can really do without this problem right now!
Regards
Chris
After a few minutes driving, I get 3 lights up. H/brake, Traction & ABS. As you might expect when this occurs I lose all ABS / TC / DSC etc. (great this week!!!)
(This has been happening for a couple of weeks now so its not particularly weather related)
Local indy reckons it's the ECU .. estimated at £1500?
so a number of questions really but in essence...
1) How likely does that sound
2) any work around ideas?
Help really appreciated - I can really do without this problem right now!
Regards
Chris
Does the light go out initially or does it stay on after each time you start the engine?
If it goes out I doubt its the ECU, it does system checks and the light goes out when its OK.
If it comes on as soon as the cars moving say 5-10mph then its probably a wheel speed sensor. On any car these can muck about. Has it had any brake work recently or driveshaft etc?
If its intermittant then it could be a number of things, Im not a BMW 'spert but Id assume theres steering angle, brake pressure etc etc sensors that all contribute to the ABS/TCS.
Check to see theres no fault codes present - most indies should be able to check - if there are, get them reset and see if they return. Never assume the codes are current!
Im sure A BMW tech will prove me wrong....
If it goes out I doubt its the ECU, it does system checks and the light goes out when its OK.
If it comes on as soon as the cars moving say 5-10mph then its probably a wheel speed sensor. On any car these can muck about. Has it had any brake work recently or driveshaft etc?
If its intermittant then it could be a number of things, Im not a BMW 'spert but Id assume theres steering angle, brake pressure etc etc sensors that all contribute to the ABS/TCS.
Check to see theres no fault codes present - most indies should be able to check - if there are, get them reset and see if they return. Never assume the codes are current!
Im sure A BMW tech will prove me wrong....
I've had my DSC and Handbrake lights come on this week too.
I did a quick search on www.bmwland.co.uk and www.bimmerforums.co.uk and both seemed to point at sensors rather than an ECU.
Have a search, I remember the ABS light being mentioned.
I did a quick search on www.bmwland.co.uk and www.bimmerforums.co.uk and both seemed to point at sensors rather than an ECU.
Have a search, I remember the ABS light being mentioned.
s.m.h. said:
Does the light go out initially or does it stay on after each time you start the engine?
If it goes out I doubt its the ECU, it does system checks and the light goes out when its OK.
If it comes on as soon as the cars moving say 5-10mph then its probably a wheel speed sensor. On any car these can muck about. Has it had any brake work recently or driveshaft etc?
On initial start up it is always fine and there seems to be no pattern to what triggers them to light up... can even come on while stationary in traffic etc. That bit I find puzzlingIf it goes out I doubt its the ECU, it does system checks and the light goes out when its OK.
If it comes on as soon as the cars moving say 5-10mph then its probably a wheel speed sensor. On any car these can muck about. Has it had any brake work recently or driveshaft etc?
Thanks for the replies so far
Chris
s.m.h. said:
Does the light go out initially or does it stay on after each time you start the engine?
If it goes out I doubt its the ECU, it does system checks and the light goes out when its OK.
If it comes on as soon as the cars moving say 5-10mph then its probably a wheel speed sensor. On any car these can muck about. Has it had any brake work recently or driveshaft etc?
If its intermittant then it could be a number of things, Im not a BMW 'spert but Id assume theres steering angle, brake pressure etc etc sensors that all contribute to the ABS/TCS.
Check to see theres no fault codes present - most indies should be able to check - if there are, get them reset and see if they return. Never assume the codes are current!
Im sure A BMW tech will prove me wrong....
If it goes out I doubt its the ECU, it does system checks and the light goes out when its OK.
If it comes on as soon as the cars moving say 5-10mph then its probably a wheel speed sensor. On any car these can muck about. Has it had any brake work recently or driveshaft etc?
If its intermittant then it could be a number of things, Im not a BMW 'spert but Id assume theres steering angle, brake pressure etc etc sensors that all contribute to the ABS/TCS.
Check to see theres no fault codes present - most indies should be able to check - if there are, get them reset and see if they return. Never assume the codes are current!
Im sure A BMW tech will prove me wrong....
Mine did this a couple of months ago. Quick trip to ForzaWest and all is well.
ETA - Link: Click.
Edited by LordGrover on Thursday 7th January 10:26
H6CJF said:
Thanks for that... Interesting.
The only work done recently was front track control arm bushes. might that have something to do with it I wonder?
Always look at the last thing done. May well be linked, may have a bad connection or damaged speed sensor giving the intermittent fault.The only work done recently was front track control arm bushes. might that have something to do with it I wonder?
Well the traction control and handbrake light on my 325Ci E46 came on yesterday after driving through some heavy snow, plus the traction control is now permanently OFF 
meaning I can't really use my car at the moment.
I googled a few forums up, and im hoping it might just be a wet or frozen sensor, but im still quite concerned..
Any one else had this problem? What did you do?
meaning I can't really use my car at the moment.I googled a few forums up, and im hoping it might just be a wet or frozen sensor, but im still quite concerned..
Any one else had this problem? What did you do?
kingofherts said:
...the traction control is now permanently OFF meaning I can't really use my car at the moment.
My E46/snow experience suggests that the car is pretty much useless with it ON. meaning I can't really use my car at the moment. On snow when wheelspin is inevitable unless I manually disable TC all I get is all power backed-off the minute wheelspin is detected. If stationary and attempting to pull away at the time, that bascially means staying stationary! TC off, driving on snow brain engaged, off we go.
Yes, I have the light on to indicate that the TC is off...
Slightly related point; when I first bought the car the light was permanently on (indicating the system was off) which obviously wasn't right. Not sure if this was sensor related or not but when I took it in for a proper four-wheel laser alignment (where it transpired that alignment was a long way out) the light then went out (system correctly functioned) afterwards. I never was quite sure however whether the previous mis-alignment had affected the TC or whether the various adjustments made during the alignment process itself had knocked/moved something related to one of the sensors that then fixed the prob. Either way, it was money well spent for the handling improvement (non-snow!) that resulted.
Slightly related point; when I first bought the car the light was permanently on (indicating the system was off) which obviously wasn't right. Not sure if this was sensor related or not but when I took it in for a proper four-wheel laser alignment (where it transpired that alignment was a long way out) the light then went out (system correctly functioned) afterwards. I never was quite sure however whether the previous mis-alignment had affected the TC or whether the various adjustments made during the alignment process itself had knocked/moved something related to one of the sensors that then fixed the prob. Either way, it was money well spent for the handling improvement (non-snow!) that resulted.
While I defrosted the windows etc. the dash was lit up like a fairy tree again this morning. Pulled off and presto! - warning lights off and all systems go. 
Seems that everybody is having gremlins in the gizmos this week!
Obviously with the weather as it is at the moment I havent had chance to do much investigation but as an experiment last night I switched the DSC off (one short press) My theory was that if the problem is related to the steering angle sensor then disabling DSC might will cut out that part of the system and therefore not get itself into fault mode and at least leave me with functioning ABS. So far..... that seems to be the case. but its early days.. sometimes it does complete a journey without lighting up and sometimes it only goes five minutes.
Thanks again for the input & good luck in keeping moving / stopping!
Obviously with the weather as it is at the moment I havent had chance to do much investigation but as an experiment last night I switched the DSC off (one short press) My theory was that if the problem is related to the steering angle sensor then disabling DSC might will cut out that part of the system and therefore not get itself into fault mode and at least leave me with functioning ABS. So far..... that seems to be the case. but its early days.. sometimes it does complete a journey without lighting up and sometimes it only goes five minutes.
Thanks again for the input & good luck in keeping moving / stopping!
I'm pretty sure I know the conditions under which mine failed last night.
I was stopped on ice waiting for the lights to change. It was in drive held on the foot brake. The front wheels were locked but the rear wheels were still turning if very slowly - I should have put it into Park or Neutral I think.
Anyway, I think the unusual state of the fronts being stopped and the rears turning for a minute or more confused the computer so it went into some kind of limp mode I'm guessing.
I was stopped on ice waiting for the lights to change. It was in drive held on the foot brake. The front wheels were locked but the rear wheels were still turning if very slowly - I should have put it into Park or Neutral I think.
Anyway, I think the unusual state of the fronts being stopped and the rears turning for a minute or more confused the computer so it went into some kind of limp mode I'm guessing.
Have you checked the battery?
My DSC light came on a month or so ago and wouldn't go out. I read a fault code of Steering Angle Sensor, reset it and it has not been on since and seems to work fine.
People at the time suggested low voltage could be a reason for the issue?
FWIW I drove for the first time in snowy conditions today and DSC was pretty useful.
My DSC light came on a month or so ago and wouldn't go out. I read a fault code of Steering Angle Sensor, reset it and it has not been on since and seems to work fine.
People at the time suggested low voltage could be a reason for the issue?
FWIW I drove for the first time in snowy conditions today and DSC was pretty useful.
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