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Old 12-22-2012, 05:31 PM
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bluebee bluebee is offline
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Originally Posted by Domer1982 View Post
I just got the ABS/Brake/DSC light trifecta problem.

About 1/10 of people have a problem with the diode readings. It's either bad technique or a meter that doesn't work well with the diodes. We have all seen this time and time again.

You are doing the RIGHT THING by testing all four of your sensors - so it's worth you trying to figure this out. I would suggest borrowing another meter. Or, yu 'can' buy a Fluke at Fryes (or a Craftsman at Sears) DMM and then use that. Those readings don't make sense for ALL FOUR wheel speed sensors - since it's almost impossible for all four to be bad at once.

Another thing you can do is try one of the OTHER six tests for wheel speed sensors - but none (by far) are as simple as this test (which, I must say, Bill - i.e., 540iman - gets the credit for coming up with).

Another thing you can do - but really it's a bit more effort - is open up your ABS control module and use a toothpick to see if the 6th aluminum wire is loose - that would tell you for sure it's the module - but I realize that's a lot of work to cut it open with an exacto knife. The good news is the rebuilders will still take it, even if you've opened it.

So, in summary, I must recommend to you two things:
a) Find a better DMM and make sure your wires are touching the metal points (thinest wire you can get)
b) Maybe consider opening your ABS to see if the 7th wire is lifted.

As for the puddle - it has nothing to do with it - as all of us, every single man and woman experiences this trifecta at one time or another. Blame BMW for putting the Bosch module too close to the engine. Blame Bosch for not heatproofing it.
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