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Discussion Starter · #1 ·
I have all of the classic syptoms of a bad ABS module(DSC,ABS and BRAKE light). I sent it off to have it rebuild and have already put it back in my car. When I first installed the module all of the lights went off. I drove about a mile or so and the lights came back on. I was so pissed when I saw this. They told me that they fixed the module and it does have a life time warranty. One thing I did notice is that the lights are cleared every time I restart my car, but then come back on after a mile or so of driving. Before the module rebuilding the 3 lights stayed on all of the time no matter what. I went by a podunk indy shop that had an OBDII scanner (or something like that, it was $5000) and they said it wasn't communicating with the car. Could this be a bad wheel sensor? If so, how do I find which sensor it is? I am not big on throwing parts at my car if they aren't needed. Any info would be greatly appreciated.
 

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My GUESS? Bad wheel sensor ... the cars must move about a mile for it to compare the readings on all 4 sensors, before it finds a problem. Your ABS unit may have been bad as well, hence the slight difference in the operation of the indicator lights.

Good luck.
 

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They should be able to communicate with the car to be honest and determine which sensor it is (if that is the problem).

Try to find another independent.

Or, you could change all the wheel sensors, I don't think they are that expensive and may be the same cost as having a main dealer diagnose the problem.
 

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How do I determine which sensor? Trial and error?
This is just a GUESS, just a GUESS!

I am assuming 3 things.

1. The sensor is not expensive.
2. All 4 sensors are the same.
3. They are easy (as in DIY) to change.

Buy one, you probably need one, anyway.

Try it on one wheel ... see if anything changes re: warning lights.
If nothing changes, replace original sensor and put new sensor on another wheel. Try it.

The only problem this approach (if it will work. I don't know as I have never had the problem, myself) has, is if two sensors are bad.

(For use by backyard mechanics only.)
 

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How do I determine which sensor? Trial and error?
Well, at the risk of being a smart alec, just connect up the car to the same GT1 you used to diagnose the ABS module and see which wheel sensor is bad. There are, unfortunately, times when a DIY needs to bite the bullet and get a diagnostic at a dealer (or qualified BMW Indy)... sometimes the $125 will save you time and money.
 

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You have a 2000. You can't communicate to the ABS module through the OBDII port if you have a 20 pin connector under the hood...

IMO you should have fixed it right the first time with a new Bosch unit. Now you have to deal with the headaches of rebuilt unit that may or may not be the issue.

Take the car to a reputable shop with BMW software, or take it to the stealership. With the right tools, this is a 5 minute fix. You're killing yourself.
 

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Well, at the risk of being a smart *****, just connect up the car to the same GT1 you used to diagnose the ABS module and see which wheel sensor is bad. There are, unfortunately, times when a DIY needs to bite the bullet and get a diagnostic at a dealer (or qualified BMW Indy)... sometimes the $125 will save you time and money.
Missed this post.... YES! ouich
 

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Discussion Starter · #10 ·
Why should I have just bought a new module. It is $225 comared to $2k. I live 2 hours away from the nearest dealer and was trying to solve my problem with the help of the M5 board and my own two hands. I will have to bite the bullet and just get the dealer to hook up to my car and tell me what it wrong. You are right, I am killing myself and wasting my time. Thanks for the input.
 

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Why should I have just bought a new module. It is $225 comared to $2k. I live 2 hours away from the nearest dealer and was trying to solve my problem with the help of the M5 board and my own two hands. I will have to bite the bullet and just get the dealer to hook up to my car and tell me what it wrong. You are right, I am killing myself and wasting my time. Thanks for the input.
I had an ABS module repaired on my 528i. It was well worth the money.

Where did you have it done? They usually have to test it before they give it back to you; it's a critical safety component. I'd have to believe that the odds are the wheel sensors. I have a spare if you want to buy it. But, I'm almost tempted to keep it since it often goes bad. I cannot stand Bosch and Siemens. They make junk. I wonder if BMW could do business with Japanese suppliers. What you'll get is a great BMW with Japanese reliability. I bet they could takeover the market share if this was the case.
 

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Why should I have just bought a new module. It is $225 comared to $2k. I live 2 hours away from the nearest dealer and was trying to solve my problem with the help of the M5 board and my own two hands. I will have to bite the bullet and just get the dealer to hook up to my car and tell me what it wrong. You are right, I am killing myself and wasting my time. Thanks for the input.
Not trying to give you crap, just trying to help you avoid anymore wasted time.

Without being able to read faults, you're just stabbing in the dark. And if your trying to save some $$$, you need to go about it the most logical way.
 

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Not trying to give you crap, just trying to help you avoid anymore wasted time.

Without being able to read faults, you're just stabbing in the dark. And if your trying to save some $$$, you need to go about it the most logical way.
It can be more expensive to do trial and error. That's how I ended up with a spare ABS sensor. I then had got the 528i diagnosed at the dealer and then got my module rebuilt.
 

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Discussion Starter · #14 ·
The nearest dealer is 2 hours away. This is why i am trying to diagnose this on my own. I called the dealer today and they said "since the car isn't under warranty and I didn't buy the car from them they won't give me a loaner car while mine is getting worked on. I may just see if they can pull the codes and tell me what it says. That might be worth a trip. I can't afford the time to take it to the dealer and wait. I use the dealer as a last resort. Last time I had my 540i in there for what felt like a vacuum leak they said after 21hrs of diagnostic time "your car is just old" and charged me almost $500.
 

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The nearest dealer is 2 hours away. This is why i am trying to diagnose this on my own. I called the dealer today and they said "since the car isn't under warranty and I didn't buy the car from them they won't give me a loaner car while mine is getting worked on. I may just see if they can pull the codes and tell me what it says. That might be worth a trip. I can't afford the time to take it to the dealer and wait. I use the dealer as a last resort. Last time I had my 540i in there for what felt like a vacuum leak they said after 21hrs of diagnostic time "your car is just old" and charged me almost $500.
Since you already got the module rebuilt, assuming this is not the problem, the next most logical thing would be to simply buy new ABS sensors. That's the most cost effective thing to do at this point and you're probably going to need new ones anyway. There are 2 sensors, not 4 as I once thought.

However to rebut myself, when my ABS module went bad it would usually give the warning light after 10 miles of driving and then reset itself before a cold start. This sounds similar to your situation.
 

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Discussion Starter · #16 · (Edited)
Are you sure there are only two sensors? I know there are two different sensors, front and back. I had the front wheels off yesterday and took a look at the sensors. They appeared to be OK, but I don't think that means much. The car has been up north for a while so the sensors would make perfect sense. Thanks for your patience on this. I just cant stand dealers.

I did a search and found that the "Tire Control" on the dash is related to the speed sensors. I have this in my display. Does this at all suggest if it might be the front or back sensors?
 

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I did a search and found that the "Tire Control" on the dash is related to the speed sensors. I have this in my display. Does this at all suggest if it might be the front or back sensors?
As your search has probably told you, the 'tire defect' system uses the rotational speed of all tires to determine if any one tire is getting 'faster'and therefore 'smaller'. If you get tire defect errors and brake errors the common component is the wheel speed sensor.

AFAIK there are 4.

C - Generic OBD-II Chassis Codes
See also: Generic OBD-II P Powertrain Codes & Generic OBD-II B Body Codes
C0000 - Vehicle Speed Information Circuit Malfunction
C0035 - Left Front Wheel Speed Circuit Malfunction
C0040 - Right Front Wheel Speed Circuit Malfunction
C0041 - Right Front Wheel Speed Sensor Circuit Range/Performance (EBCM)
C0045 - Left Rear Wheel Speed Circuit Malfunction
C0046 - Left Rear Wheel Speed Sensor Circuit Range/Performance (EBCM)
C0050 - Right Rear Wheel Speed Circuit Malfunction
C0051 - LF Wheel Speed Sensor Circuit Range/Performance (EBCM)


Have you pulled any codes just to see if anything shows up?

Good Luck

A
 

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Discussion Starter · #18 ·
OOOOOWW! I had the codes pulled at a little indy shop, but they had no way of interpreting the codes. I need to call them back and have them tell me what the codes were exactly. Your chart may have saved me. Thanks for the info. This is great!
 

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As your search has probably told you, the 'tire defect' system uses the rotational speed of all tires to determine if any one tire is getting 'faster'and therefore 'smaller'. If you get tire defect errors and brake errors the common component is the wheel speed sensor.

AFAIK there are 4.
That's right; there are 4. I got it mixed up with the 2 brake wear sensors.
 

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OOOOOWW! I had the codes pulled at a little indy shop, but they had no way of interpreting the codes. I need to call them back and have them tell me what the codes were exactly. Your chart may have saved me. Thanks for the info. This is great!
Type in the following 3 words into the search feature here.

wheel speed sensor

I'm no genius, just a really good searcher!

:)

A
 
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