Got the dreaded abs/4x4/flat tire... Checked code and got 6d9b wheel sensor left supply.

Since im not home i could only take off the sensor, the "ring" looks fine, did find some metalrust in the hole i removed, saw one spot on the ring with clean metal, saw nothing on the senor and still protected by rubber, same with connections, looked clean.


Also checked with protool and left front gives no signal for wheel speed.

Weird is i drove several miles with it on, parked it for 2 days and then it was off for a few mile before coming on again.

Is there a way to test the sensor with protool/ista/ inpa or multimeter?

Aswell test for voltage from ecu to sensor?


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Check resistance 980-2350ohms. If not then replace sensor. If it is then test voltage by turning the wheel

 

Righty... So the wheel turn, do i just read from the connector from ecu then or all connected to se 12v thrue sensor?

Also i heard bad things from aftermarket sensors?

 

Put positive lead on sensor connector while unplugged and negative lead on any ground. Turn wheel and you should get a voltage reading 190-1140mV. If not something is wrong inside and it's not the sensor. If you need a sensor get BMW or OEM only. Bosch is OEM

 

Thanks, yeah im searching for a bosch. But all here in sweden seem to be out of supply.

 

You can get a Delphi one also

 

Did you attempt to calibrate the FTM?

 

I did thrue the menu, got a error. Restarted and could clear it, then it came back driving the long trip and couldnt clear it, after beeing parked for 2 days i started it up and all was gone for a few miles.

Gonna check when i get home, but first i need to go away on work.

Was considering changing sides on the sensor, like one do with injectors to se if the fault follow one, if the multimeter doesnt work.

I also believe they put at 1mm shim on the one o removed, it was between the sensor and the "tower"

 

I feel that would be easier than measuring voltages due to the intermittent nature of the problem.

 

Did a reading on the one broken, got 560ohm. Also found a crack in the ring. So guess i need a new ring, wheelbearing and sensor.

The sensor that was there was the manufacture
vemo v20-72-0514-1 987084692

When checking it is compatible with the oem nr
34526771700 aswell the old nr 34526767578

Surprisingly when using sites here in sweden that choose parts after your license plate still show parts with other oem numbers.