3-Series (E46, E90)Chat relating to the BMW 3-Series from 1999 to Current. Models include: BMW 316i, BMW 318i, BMW 318Ci, BMW 320i, BMW 323i, BMW 325i, BMW 330i, BMW 328 Ci, BMW 328i, BMW 325i/xi, BMW 330Ci, BMW 320d, BMW 330d, BMW 335d.
I've recently rejoined the BMW club after parting for a couple of years and about 2 months ago I purchased an E46 320i Tourer 2001. It has full BMW history (yes - company owned) and has 100k on it.
Today, three warning lights came on on the dashboard. They are the ACS Traction Control, the ABS and the Brake Pad lights. I believe that this 'may' mean that one of the wheel sensors could have failed. Either way - I now have no ABS and no traction.
I wondered if anybody had experience similar ?
Every time I restart the car, the lights go off for a few seconds, then came on again. The Brake pad warning light (I think ?...the one with exclamation mark next to the ABS) first comes on Orange, and then within a few seconds turns to red.
Any advice would be appreciated. I'm fairly mechanically minded, and would be chuffed if it is something I could repair myself (especially just after xmas etc!)
Hi and welcome!
Go to the "search bar" above and type there "abs problem", you will get lots of info regarding this matter posted already on this forum.
BTW how is the brake fluid level on your car and charging system?(battery and alternator).Check it first before digging deeper !
I'll check out the condition around the wheels/sensors, brake fluid and the battery voltage levels over the weekend. I'll do anything to stop the stealerships charging me the ridiculous costs like they do.
The BMW guy said that this is also the reason for why my ASC isn't active. And also why my car has cut out three times recently - something to do with the ABS unit and the ECU not communicating etc. Does this sound about right?
He also mentioned that if I did manage to get an 'off the shelf' replacement, that it may not be coded the same - but he was unsure as to whether they are possible to be 'recoded' once they have been coded - whatever that means.
5 years of problem free BMW ownership (except for having to replace a fuel pump relay on my old E30). And then just rejoined the BM club to have this happen. It must be the most expensive part on the car! Bad luck hey.
On this car ECU controls ABS and ASC is a separate thing, I wouild search first for more obvious causes of the problem before changing this expensive unit.I do not want you to end paying huge bill and the problem still being there after that.Lets hope the diagnosis is correct.
Still not got to the bottom of this one unfortunately....
Due to recent circumstances I've been unable to get a 2nd opinion. And as you say, I'd rather not fork out for an ABS unit just yet.
I have though, noticed something else now. Occasionally the lights will go out, but usually come back on within a very short time. In fact the lights stayed off for about a week recently until I jet washed the car and then they came back on again immediately. It may be co-incidence but the very first time this happened I had driven through a Ford that day about half a foot dp ??
Anyway, what is happening now is an occasional grinding noise through the brake pedal, when I brake after first starting the car. It doesn't do it all the time, but when it does it usually goes away after around 2 or 3 presses of the pedal. Whilst it grinds the ASC light flashes like it does when you wheelspin. The grinding feels like the when the ABS kicks in. But also, after that it sounds like metal grinding against metal - like when say when your discs go rusty until you brake and 'clean' them.
I'm totally lost now, I dont know how wheel sensors attach to the wheels (my BMW DIY CD wont work on my PC ;( ) but wondered whether it may be a lose one of these or an exposed wire not working when it gets wet etc.
Has anyone experienced anything similar. I have 2 independant BMW specialists I can use. One say the ABS unit. I can't get to the other for weeks. And I really dont want the Stealerships to take a look as no doubt it will cost more than the car.
Typically this situation is caused by a faulty wheel speed sensor, without proper wheel speed signal the ABS/ASC cannot function properly. with your car up in the air, there is a 4mm allen screw back around toward the top of the dust cover. Remove the screw, and gentally pull the sensor out and check the condition of the toothed wheel (check for missing teeth or debris build up) check the condition of the sensor surface. The connector is held in the same holder as the brake pad sensor. Good luck, hope this is helpful
Just for the record, and to help others, I thought I'd conclude the problem.
A few days ago my gearbox (auto) went into Emergency Limp mode. I took it to the BMW Technician that I use, and by this time I had received my replacement ABS unit which he had diagnosed as being the problem for the cutting out, and ABS and ASC dashboard lights. He tried to change the ABS unit but it was a slightly different part number (it was cheap so worth a try), and the car wouldnt accept it. He then put the old ABS unit on and recoded it and since then it has worked fine - no ABS and ASC problems.
On the same visit, the code was read for the gearbox problem, and pointed to a rear wheel sensor. This was changed and gearbox now fine too.
I can't help wondering whether, as suggested on this site, that the ABS ASC problem was the rear wheel sensor all along ?
Either way, sorted now. And thanks for the help guys.
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