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Discussion Starter #1 (Edited)
I'm trying to trace the source of the yellow DSC/BRAKE warning lamps staying on. Alignment is not causing it.




One of the things I did before leaving for Canada was changing the brake fluid at a local shop and I believe the method they used was the pump and bleed method - where one guy was in the car pumping the brake whiles a guy went around draining each brake line.

I know lots can go wrong during this job but what would a sure connection or sign between a bad brake fluid job and the DSC/BRAKE lamp coming on after 700+ miles and a few days later of driving?

How can I troubleshoot the connection as well?

Here are some pictures of when they were doing the job:





 

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Check your fluid level. If it's low it would throw the DSC Lamp. Not sure if the BRAKE light is added in the 2-stage DSC. Are you capable of turning off the DSC in two stages?
 

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Honestly, best thing to do would be to have the codes read. Here's what I posted on bf.c:

If they introduced air into the system, then it is possible that some air made its way into the DSC system. Bleeding the abs system isn't difficult, but it does require BMW's diagnostic software. I've personally used it to get air out of my ABS module.

I would think you would've noticed a soft pedal if you had air though
 

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Discussion Starter #4 (Edited)
Check your fluid level. If it's low it would throw the DSC Lamp. Not sure if the BRAKE light is added in the 2-stage DSC. Are you capable of turning off the DSC in two stages?
nope. The glove box manual says when both the yellow DSC and BRAKE lamp are on it is communicating that the DSC Module is not functioning properly and/or dynamic stability control is not currently available given the current conditions in and around the car. These conditions can be dozens of things from using worn tires on wet/icy roads to old battery to faulty alignment to dirty speed/abs sensors.

I get that the point of both the DSC and BRAKE yellow warning lamps being on together is to distinguish it as a warning lamp from the normal yellow DSC lamp being on alone when you push the DSC button which simply communicates that the driver has pressed a button to turn off the DSC module.

I will look at the speed sensors tommorrow and clean them thoroughly when I check them.

I just want to be sure of every angle before calling the BMW Dealership to read the codes knowing that it will only lead to them telling me something expensive needs to be replaced.
 

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Discussion Starter #5
Honestly, best thing to do would be to have the codes read. Here's what I posted on bf.c:

If they introduced air into the system, then it is possible that some air made its way into the DSC system. Bleeding the abs system isn't difficult, but it does require BMW's diagnostic software. I've personally used it to get air out of my ABS module.

I would think you would've noticed a soft pedal if you had air though
Hey Terra,
I did not note a soft pedal and I've driven the car close to 1500 miles to Canada and back since then.
 

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I'm having the same problem right now, the dsc with the yellow brake light. So far I've checked and cleaned the wheel speed sensors, disconnected the battery to see if the lights would just go away, and just as a maintanence item changed the brake fluid but none helped. Like you I'm avoiding going to the dealer so they can tell me I need to replace a $600 part. Good luck, I guess first one to fix it wins?
 

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i had my DSC and brake lights come on before and it was because of low fluid after abit was lost doing a brake job.
 

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Mine was low fluid as well after replacing the brake booster. topped it off and it went right off! It does not need to be very low to detect it! Its really touchy!
 

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So there was just a post a couple of days ago...the guy had the lights, cleaned the connector in the wheel well...I think it's right next to where the brake pad warning sensor plugs in (in back of wheel well).

He cleaned the contacts in that electrical connector and that was it.

In your case, I could see how hitting a large metal object, tossing rubber pieces around for 500 miles, might have kinked the wires and thus is setting off the sensor.

I've read repeatedly here that cleaning the speed sensors don't do anything...and I have to say that those who say this seem more adamant that it doesn't work, than those who say it does. IDK.

Me? I'd start looking at the connector and wires in that rt. front wheel well were I you.

I believe the front speed sensors 'magnets' are built into the hub/bearing assembly (one part). I don't know where the 'sensor' itself is attached, but it has to be right there somewhere!

Only other thing I can think is that you got new front tires and maybe not in the rear. I believe it was in your thread that someone mentioned that if the tires are far off in diameter, that that can set off the dsc. So maybe your tire pressure is the same all the way around and the fronts are larger than the car wants them to be, relative to the rear? Total guess, but you could try just lowering the pressure in the front and raising it in the rear? IDK...trying to help!

Finally, I suppose if they bled the wrong way, and the guy inside lifted his foot while the bleed nipple was still open, that air might have gotten into the abs/dsc system, in which case I think you'd need software to cycle dsc while bleeding to remove it.

I know you've searched for those three lights in title search...there are a lot of threads on it. I haven't studied them thoroughly since I haven't had that issue.
 

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Didn't you say you crashed into road debris that forked everything up ? It was a poor brake fluid job but I don't think that is it. Something in your suspension is bent.
 

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Okay, so I don't want to scare you or anything...But when I was negotiating the sale of my car, I noticed it had the DSC lamp lit. It drove fine, braked hard, but it didn't engage if you went a lil quicker than recommended.

I had the used dealer make sure that it was fixed before I went on a 235 mile trip back to Morgantown, WV. So he took care of it. Told me it was low Brake Fluid Level and when I picked it up, it started up fine, no lights, but when I made my way home, it came back on. Stopped the car, and restarted. Light came back on with in several hundred feet of driving.

Returned the car and told him it's still on. He troubleshooted for a day before taking it to the dealer. As it turns out, I needed to have both DSC Modules replaced (Early e46's have two modules, one under the Brake Booster and one in the drug bin) and coded to my vehicle.

Total bill: $73X.XX. Thank goodness I didn't have to pay that.

So here's to hoping it's just low fluid!
 

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do some simple checks, what it sounds to me is that you possibly have a broken tone ring. the other thing you need to have done is scan the ECM and make sure the moduals arnt bad becuase hes right early modle e46 had issues with the moduals. make sure the booster is topped off. and go from what ever codes the dealer says you have. i can assit you if u give me the codes that are in the ABS/ESC system.
 

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It might not be related to the brake job at all. Most common cause of those lights is the wheel speed sensor. When I got those lights it was the steering angle sensor. Since you didn't have any problems on your trip, and since the abs light isn't illiminated, I'm inclined to think your brakes are okay. Road debris may very well have killed a wheel speed sensor.

Jake has pasoft right? It should be able to read the errors from your DSC module. It doesn't have the capability of bleeding the pump, but that may not be necessary.
 
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