Brake Light & DSC light (Z-3 roadster)

The brake light & DSC light came on simultaneously the other day on my 2001 3.0 Z-3 Roadster. The car has 44,400 mi. on it. Brakes work fine & there's no slipping of the tires in the rear end. The DSC light has come on befoe but eventually went off. The front pads were replaced 14k miles back but the car brakes with no problem & does not pull to the right or left when stopping. Any idea why the lights are on?? Can I use a peake tool to turn off the lights? I am open for suggestions.

When the light comes on like that it means that something is wrong with the system. If it was just the DSC light it would mean that it works just like when you have DSC turned off. With the brake light on along with the DSC, it could mean other things. My guess would be that one of the wheel sensors isn't working right. I will be trying to track down why my DSC is on this weekend. From what I can tell, check the wheel sensors first, but it can also be the steering angle sensor or the lateral acceleration and rotational rate sensor (which is under the left seat).

Other posts on the board suggest pulling the codes to see where the problem is. I tried to pull the codes with the key on, but the engine off. There were no codes. I'll try again tomorrow with the car running, if still no codes I'll start with the wheel sensors.

Originally Posted by khammack

When the light comes on like that it means that something is wrong with the system. If it was just the DSC light it would mean that it works just like when you have DSC turned off. With the brake light on along with the DSC, it could mean other things. My guess would be that one of the wheel sensors isn't working right. I will be trying to track down why my DSC is on this weekend. From what I can tell, check the wheel sensors first, but it can also be the steering angle sensor or the lateral acceleration and rotational rate sensor (which is under the left seat).

Other posts on the board suggest pulling the codes to see where the problem is. I tried to pull the codes with the key on, but the engine off. There were no codes. I'll try again tomorrow with the car running, if still no codes I'll start with the wheel sensors.

Thanks much for the info. I'm having the exact same problem.

I just checked and cleaned all of the wheel sensors, but it didn't help. I'm thinking the next step is to replace the steering sensor, but it is $170. The wheel sensors are about $110 each. Does anyone know if there is any way to test these sensors to tell if they are bad or not. Trial and error replacements can get expensive.

I hope you come up with an answer; mine does this intermittantly as well. Typically applies the anti locks HARD on the right front wheel for a few seconds, then the lights come on. I'm thinking a wheel sensor on the Rf wheel, but at $100/shot, I hate to just start replacing parts.

I tried to test the wheel sensors based on a post I found for another model of BMW, but the post said there were two pins in each sensor and we seem to have three. I did check all four corners anyway and they all tested the same, but not what the post indicated. I'm thinking my wheel sensors are OK since I got the same reading on each. I did find that there are also sensors on the bottom of the break fluid reservoir, but they look OK. No idea how to test them. I think I'm going to need to take mine to the dealer because it seems to be either the steering sensor (and the computer needs to be reset when it is replaced) or the control unit.

Others have indicated that you can pull codes to see what the problem is, but I tried to pull codes with two different code readers and both reported no codes. I just have a solid DSC light.

There is a local independent BMW service place that is prettty good; they have confirmed they can work on it. i may take mine to them. At time, the car slamming on the front brake is troublesome

I'm not sure what would cause that, but I would take care of it as soon as possible. It sounds like it could be dangerous.

If you are interested in seeing where the speed sensor is located...then check with Randy Forbes on this site. Or you can check it out on http:/forums.bimmerforums.com/forum...t=speed=sensor. However, this info. is on another forum..."bimmerforums". Randy Forbes who is a member of this forum is apparently a member of the other one also. He posted pics of the speed sensor. Hope this will help you & me both....let me know if it does...looks fairly easy to replace if needed??

Well, after not being able to find anything wrong on my own (except the DSC light on) I took it to the dealer. They put it on their fault reader and didn't find anything wrong except for one code - "Vehicle Power Above 18 Volts". They checked the charging system and it was OK. They then recalibrated the Steering Angle Sensor to fix my DSC light on problem.

I had that same thing happen last year. I cleaned my wheel speed sensors and evened out the tire pressure (one tire had lost a fair amount of air for some reason), and all has been good since.

Been there, done that. I even tried to test the wheel sensors using a write up I found for an E46 (I think). It wasn't good for Z3s, but I did get similar reading on all 4 wheels, so I thought the wheel sensors were most likely OK. I couldn't find any way to check the steering angel sensor or to recalibrate it, so no choice but to go to the dealer.

At least I got to sit in a 1 series. It looked nice. I'll bet they go fast once they get some in they can actually sell (they said this one was demo only and they can't sell any until after the announcement in about a week).

2001 BMW Z3 2.5 DSC Brake Light Brakes activating

Front Brakes Activating hard, DSC light blinking, then DSC and Brake light stay on. It happens random. every 30 miles every other day.

Solution:
Rotational Rate Yaw Sensor Under seat is malfunctioning
Part Number 3452 6 754 289

The mechanic informed me he would charge $1000 to replace but i fixed for only $60 and this is how:
1) The part retail's for $600 dollars - Mechanic told me that a used part is no good and that it has to be programmed. HE IS WRONG. That yaw sensor doesn't have to be programmed and you can do it yourself.
2) FIND A USED SENSOR - Go on EBAY - I found the part for $60 , but i was lucky. Other used yaw sensors go for $260-350. Make sure that it is a POWERSELLER for used parts and that it is a working sensor tested before you bid on it.

The sensor is a universal sensor that was placed on alot of BMW models. Just make sure it's the same part number. The listing on ebay said it came off a 3 series when i drive a Z3 but its fine.

3) The sensor is located under the driver seat and carpet. REMEMBER to disconnect battery before removing seat or the airbag light will stay lit.
4) The carpet under the seat is indented and no tools are needed to reach sensor.
5) The sensor has 2 bolts and a electronic connection (EASY TO REPLACE)

can also be weak battery

Just watch out with a used sensor. My yaw sensor was causing problems, but only after around an hour of driving. Park up for an hour and good as new again. I now have a new sensor as a permanent fix and kept the old one as a 'spare'. Just watch out someone else didn't have that intermittant problem and sell a semi-faulty unit.

Chaps, My 320ci is also having the same problems. It happened today after i inflated my tyres (32 at back and 29 in front) and i was driving behind a Hay Truck for a while which was spilling Hay everywhere and so i'm wondering if there may be Hay stuck in my Traction system? Is that possible or am i just making up problems here?

Anyhow, If i wanted to clean the sensors, where would i find them? Thanks

my Brake light is on & my DSC (traction) light is on & my airbag light is on. I took it to German Auto repair and they fixed the Check Engine light but could do nothing with the other 3 lights..... whats the deal? theyve been on for a year now and im ready to sell it but hard to sell with the dash lit up like a christmas tree!!

I have a brand new battery, 4 brand new tires, fresh alignment, brand new front brakes and rotors, new water pump, new fan, new belts and a fresh new oil change.... what gives?

I believe that your DSC and Brake lights indicate a speed sensor has gone out. Mine did this intermittantly for about 4 months then went solid. After doing some searches in this forum and Bimmerforum, I figured it was the speed sensor. I called my local indi to tell them and make sure he had a speed sensor in stock. Took it to them, they validated on their machine (same one as used by the local deal and direct from BMW) and had it turned around in less than an hour.

The airbag light has been known to indicate a bad seat connector for either the passenger or driver side. At least that is what I've seen in this forum. Do a search and see.

If your indi hasn't figured it out, I would take it to a dealer or a different indi that specializes in BMWs. Mine does BMW, Mercedez and Volvo. Nothing more. They have factory diagnostic machines for all makes, not just the after market readers...that don't always have the right BMW codes in them.

Good luck.