I have a 2003 Mini Cooper (plain) with the CVT transmission. I bought the car used a year ago with 48K miles on it and have put another 12K on it in the last year.

About six weeks ago I started having problems with the ABS system. From reading other threads, I realize the most likely problem is a bad wheel speed sensor (the ABS and tire pressure lights come on and go off, intermittently; my car doesn't have DSC so I don't have the usual "trifecta").

There is no authorized Mini dealer in my area...I'd have to drive 350 miles, each way, to get to one. I've been taking the Mini to local mechanic who specializes in VWs and who always gave excellent service and advise on a Golf TDI I had before the Mini. He services BMWs and does routine service on Minis for a couple of customers.

I ignored the ABS/tire pressure lights for about a week, but then I started feeling "problems" occasionally when braking. These problems only occur when the lights are OFF. I've since learned that what I'm feeling (a grabby, scudding, scraping kind of sensation/noise) is the ABS system activating unnecessarily, and actually releasing one of the brakes. Apparently, this makes it feel like the remaining brake(s) are grabbing?

The computer on my Mini has been scanned, twice, and has NO codes logged in it. The mechanic does not have a program specifically for testing/reading ABS systems. He said he was going to install one, but it seems that isn't going to be happening this month.

He's already checked all the sensor wires/connections for dirt, abrasion, etc. and says they "look" fine. He said he repositioned the wires so they are "out of the way", and since then the lights have been coming on less. Also, since the wires were neatened up, the ABS light goes off once I start driving forward when I restart the car after a drive where they turned on.

However, I am still bothered by the ABS activating unnecessarily every couple of weeks. Sometimes the lights come on after this happens; sometimes they do not.

My mechanic says that when the ABS light is ON (with or without the tire pressure light, I guess) it means the ABS system is deactivated. Prior to the sensor wires being neatened/repositioned, I drove around for days with those lights on, and I could not feel ANYthing different in the way the car drover or braked. Ditto when the lights turn on now; even though the lights are on for much shorter periods of time, there is still no noticeable difference when braking or driving while the lights are on.

I talked to the mechanic today, and he reiterated that when the lights are ON, the ABS system can't "act up". He said if the lights are off and I feel the ABS system activating unnecessarily, and it becomes "bothersome", I should just pull over, park, and turn off the car. He said the ABS system will "reset" when I start up again and the unnecessary activation should stop. He suggested that if it got really bad, I could just pull the fuse for the ABS (that is, if I actually knew which fuse it was!).

I read some threads that indicated you could not/should not turn off the ABS system, via the fuse or a switch, because it will affect the DSC...but since I don't have DSC THAT doesn't matter. It was also suggested that braking would be affected because some electronic braking distribution wouldn't be working? If I understood what I read, the rear brakes would be prone to locking up? If that is true, why doesn't this happen when the lights are ON and ABS is supposedly deactivated.

Is there a difference between the level at which ABS is deactivated when the ABS light is ON and the way it would be deactivated if the fuse failed or was pulled? Is there a difference between what the ABS light being ON means when it is ON in conjunction with the other light(s). In other words, is my mechanic mistaken when he says the ABS system is deactivated when these lights are ON? If the ABS fuse failed or was pulled, would the ABS or any other lights come on and stay on? Could my problem becaused by a faulty fuse? And BTW, which fuse IS the ABS fuse?

 

On my 2006 MCS w/manual transmission, if you pull the ABS/DSC fuse, the car goes in to limp mode.

I tried pulling the fuse to get around a bad wheel speed sensor that was intermittently causing the DSC and ABS to go off and on but unfortunately that made things worse (limp mode.)

 

Thank you very much for passing on this information. It is definitely something I wouldn't want to learn first hand. I guess I'll just have to live with the intermittent ABS activations, or have my mechanic loosen a wire to cause the warning lights to go on permanently. That doesn't seem to cause "limp mode", and as annoying as the warning lights are, they aren't as annoying as the the brakes "grabbing" for no reason. Of course, this would just be a work around until I find someone who can actually diagnose the system and figure out which sensor it is. I worry, though, that it is so intermittent that the sensor won't fail during the diagnostic test. Also, I haven't found any other threads where drivers reported that their ABS system was unnecessarily activating when they had an intermittent sensor problem.