Wheel Speed Sensor problem?

[petrolhead]

Not come across this before but a high resistance ground connection somewhere in the system can throw up weird and wonderful issues like this. It throws out the reference voltages inside the module and can give some incorrect sensor readings and can cause errors on the canbus. I've had some fun issues on peugeots and renaults, french wiring isn't the best in the world.

[petrolhead]

Originally Posted by terryo

what gear??
the speed sensors are built into the bearing & hub. in the back of the wheel bearings are a row of metal lugs that the sensors detects as the wheel turns. that info is used to determine both road speed and wheel slip, and its that info that "drives" everthing via the various computers

It appears hilton replies with any old crap to random threads along with his other mates just to spam the board with links to junky chinese scantools.

[turquise1]

Where are the ground connections to check? I have heard about ground connection issues but dont really know what/where to check..

Ozzie..

[petrolhead]

I don't know either you'll need a good wiring diagram and patience. I was just adding my experience from problems on other vehicles, as it sounds like you have exhausted most of the other possibilities. study the diagrams and make a checklist of voltages and resistances to test and go through them methodically highlighting any discrepancies. to look for bad joints and connections I prefer doing a volt drop test with the item under load. to check for a bad ground set your meter to voltage, put the negative lead of your meter to battery negative possibly extend it a bit and backprobe the ground pins at the module and sensors with the meter set to dc volts and the engine running, the voltage should be less that 0.01 volts or there is resistance in the ground which can give a floating reference.

[turquise1]

I have checked the main ground wire close to the module box (passenger side) and it looks perfectly healthy. So there goes another reason for these issues..

Ozzie..

[turquise1]

Update : I still have the issues, and here are more errors I can see with my Bmw Scanner :

EGS -> 3B/81 - Stalling speed

ABS -> 21/FD - Wheel speed sensor front left, open circuit

LEW -> 09/AB - No CAN message (ASC)

IKE -> BD/D0 - Electronic braking-force distribution
8D/90 - EGS signal line disturbed

LCM -> 28/01 - Thermal oil-level sensor defect
Shadow-memory:
59/01 - Transmission failsafe program

Ideas?

Ozzie..

p.s. I have tested and replaced the speed sensor and no change..

[upallnight]

Looks like the wiring for the front left wheel sensor may be broken, that is why you have an open circuit, and why replacing the wheel sensor didn't fix the problem. Did you check the pins in the connector to the wheel sensor to see if they might have been damaged? If you replaced the plastic housing for the connector did you get the wiring back in the right order?

[raperka74]

Im having almost the same problem, I bought a 2001 x5 4.4 with tranny problems.

The car will take properly the gears only in manual mode, it will slip or will rev but wont go in first gears.

I change the oil and tranny filter, then the speed sensor and the wiring harness temp sensor.

After changing the parts we rescan the ecu but did not got any more errors.

THe one we had was the 59 stalling speed
plausibility error present.

Appreciate any info before going into changing the tranny.