DSC Warning Lights on

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Bumpa
Joined: Fri 23 Jun, 2017 20:31
Posts: 70

  Z3 roadster 2.2i

DSC Warning Lights on

Post by Bumpa »

The car is a 2002 2.2 Sport. I have the brake fluid and the DSC lights permanently on, which the handbook tells me is caused by the DSC system. I have taken the car to a local independent workshop that I have used for years and have always found to be excellent in the past. The story so far...

My car has now been in the workshop for eight days and we are no further forward. The code reader pointed to a faulty lateral acceleration sensor, which as you know is under the flooring on the passenger's side of the car. When the guys lifted the flooring they found a swimming pool with the electronic bits submerged. They dried it all out, cleared the codes, but the same error kept coming back, so they bought a new sensor.

This hasn't fixed the fault, and they now wonder if the water has corroded the wiring connectors. So far they haven't been able to find a wiring diagram of those components for my particular car, a 2002 2.2 Sport. Can anyone point me to the correct diagram?

I don't think they know how to proceed. Has anyone here had the same problem? How was it sorted? Answers on a postcard please. How I hate electronics! :(
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motco
Joined: Tue 18 Aug, 2009 18:12
Posts: 728

  Z3 roadster 2.2i

Re: DSC Warning Lights on

Post by motco »

I doubt that this will be a lot of help but I had these symptoms on my 2.2 Sport accompanied by occasional engine misbehaviour. It was the throttle body faulty which sounds bizarre but all these systems are inter-dependent. If the pedal and the throttle position are out of sync and the revs don't correspond to either the processor assumes all sorts of scenarios. If you have been having even occasional throttle response events it may be worth a look. All that being as it may, mine did return fault codes related to the throttle body.

Good luck anyway. If you are anywhere near Amersham (Buckinghamshire) go and see Phil at CPC.
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Robert T
Site Admin
Joined: Mon 12 Jun, 2006 10:35
Posts: 10170

  Z3 roadster 1.9
Location: Cheshire

Re: DSC Warning Lights on

Post by Robert T »

Error codes for a specific sensor are normally caused by the sensor emitting implausible values, whether that being due to a sensor fault, wiring fault or something connected to the sensor not generating the right inputs. So, if the car flags up a specific sensor, it is usually something closely related to that sensor which is at fault.

With the acceleration sensors, note that there are two. Make sure they have changed the right one!

From memory, I seem to recall that there is some kind of calibration process that has to be carried out on the new sensor. I don't recall if this needs software, or if it is automatic, requiring the car to be driven. I do know that INPA will show the individual outputs from the sensors, so you can check whether they are working and that the values are within the acceptable range.

Edit: some more info here.

Cheers R

Sent from my SM-T810 using Tapatalk


Arctic Silver '99 Z3 1.9 & Black '59 Frogeye 1275cc
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Bumpa
Joined: Fri 23 Jun, 2017 20:31
Posts: 70

  Z3 roadster 2.2i

Re: DSC Warning Lights on

Post by Bumpa »

Thanks for those thoughts. I am not close to Amersham, living as I do in Troon, SW Scotland!

The link that Robert sent would be a lot more useful if I could see the pictures. Is there any way to make them appear? I know that Photobucket have screwed up lots of forums - is there a work-around?

Mike
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motco
Joined: Tue 18 Aug, 2009 18:12
Posts: 728

  Z3 roadster 2.2i

Re: DSC Warning Lights on

Post by motco »

Yes, sorry Mike, I should have checked your profile before I posted!

I seem to recall that there may well be a work-around but I cannot remember what it is. I think it involves the original poster of the images to add some code to the thread they're embedded in.
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Gazza
Joined: Tue 04 Oct, 2005 20:58
Posts: 9521

  M roadster S54
Location: Romford Essex

Re: DSC Warning Lights on

Post by Gazza »

viewtopic.php?f=2&t=45394

Photo bucket fix
Gazza

"Understeer is when you hit the wall with the front of the car, oversteer is when you hit the wall with the rear of the car. Horsepower is how fast you hit the wall and torque is how far you take the wall with you"

Z3 S54 M roadster Image, BMW Z1, BMW M3 CSL, Z4M Coupe
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Bumpa
Joined: Fri 23 Jun, 2017 20:31
Posts: 70

  Z3 roadster 2.2i

Re: DSC Warning Lights on

Post by Bumpa »

Robert said "From memory, I seem to recall that there is some kind of calibration process that has to be carried out on the new sensor. I don't recall if this needs software, or if it is automatic, requiring the car to be driven. I do know that INPA will show the individual outputs from the sensors, so you can check whether they are working and that the values are within the acceptable range."

Spot on Robert. I was discussing the problem with the workshop guy on the phone and I asked him if a BMW agent would be able to get better information out of the car with better equipment. I almost heard the light bulb of an idea spring into his head. He scratched around and found a more sophisticated code reader / scanner and bingo, it told him that the sensor was out of calibration. It registered a sideways movement when the car was stationary. He calibrated it with the scanner and out went the lights -whoopee! :D Now I have to dry out the flooring and find out where the rain gets in.

He then did the MOT and it passed with just one advisory - apparently the RH front brake is very slightly binding. Not enough to make the brake hot, but enough to show as a difference on the rollers. Well, I'll take a look at that once I have it back, which won't be till Wednesday as I can't get down to the garage (11 miles away) until then.

Things are looking up, especially since the Autoguard warranty is going to cover the cost of the new sensor and fitting. Happy days.
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