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I recently purchased a 2001 530i. The trifecta of ABS lamps is on, as well as a check engine light, a dead speedometer, non fuctioning odometer (reads but does not advance mileage), and a fuel gauge that becomes very erractic when the tank drops below ¼. (needle swings from empty to half full when you go around a corner). I scanned it with a Foxwell and got the following codes on the DME scan: 82- DME Signal CAN ASC/DSC, and DME: signal roadspeed. I attempted to scan the ABS module with the Foxwell and got a “no communication” error. I then attempted to read the signals from each wheels speed sensor at the ABS module connector. I got NO response on any of the 4 wheels when peforming the diode test or the resistance test. I used a fairly new mid grade Craftsman DMM with diode testing capability. (which has always worked fine) I then disconneted the LF wheel speed sensor and tested that while spinning the wheel and got no reponse. I then removed said speed sensor, cleaned it (it was not very dirty) tested the resistance off the car (no response), reinstalled it. No change. The prior owner took it to a BMW dealership in 2019 for “multiple dash lights” and the dealership invoice says “ found no communication with vehicle, then found shorted abs module”. The issue was not repaired at that time.

So… I’m very perplexed at this point. If the dealership diagnosis is correct, I have a bad ABS module. If my own testing is correct, I also have 4 bad wheel speed sensors. Highly unlikely. What am I missing here? Did I test wrong or is my DMM not up to the task? I don’t want to just start throwing parts at this thing. Any guidance is much appreciated thanks!
 

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2001 BMW E39 540i Automatic Sedan, 200 k miles
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2,372 Posts
You have multiple problems on this car.
Assuming no battery / electric connection problems, the most likely are : defective LCM (Light Control Module), one or more bad speed sensors that in turn trigger ABS errors, and hence makes one think of a possibly bad ABS....

You need to get hold of INPA or other BMW specific scanner to read the error codes from all the modules :Engine, Transmission, LCM and ABS are the most important.
 

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‘89 325i, ‘98 528i, ‘99 528i, ‘03 325i
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564 Posts
Yeah, get INPA running and use the round diagnostic plug under the hood, I don’t remember when it changed but the OBD port under the dash doesn’t talk to the whole car.

Your ABS/speedo/odo gets its signal from the left rear wheel speed sensor.

Your cruise control gets its signal from the right rear wheel speed sensor. (Does cruise work?)

I bought 3 different aftermarket rear wheel speed sensors and none of them worked. Went to the dealer and got factory ones, all problems went away. If the previous owner tried aftermarket sensors on the rear it’s likely that there is your problem. In my experience the front wheel speed sensors do not have to be factory/BMW.

ABS control modules do/can fail but until you get INPA running and connect to the round connector I would be hesitant to say yours is bad.

The fuel gauge may be acting normally, mine goes wonky on turns as well when the tank is low. It’s just fuel sloshing through the line that connects the right and left sides of the tank.
 

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For the fuel level, take out the back seat, open the passenger side cover to fuel tank, take up fuel pump and fiddle a bit with the measuring mechanism, put it back in and close lid. On mine, it would not go lower than 1/4 tank.
 

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2001 BMW E39 540i Automatic Sedan, 200 k miles
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Yeah, get INPA running and use the round diagnostic plug under the hood, I don’t remember when it changed but the OBD port under the dash doesn’t talk to the whole car.
....
No, the OP has a 2001 E39. So the OBD port under the dashboard is in fact the only port on the car- and works with INPA, provided using a K-Line cable to connect the car to the INPA laptop.
Use or buy a "K+DCAN INPA cable with a switch". Google it.
 
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