I had the 4 lights come on the dash couple days ago and took it to a
mechanic friend who ran diagnosics with a snap-on reader. The "ABS",
DSC triangle, "BRAKE" and something else, which I was told all come on
together when the speed sensor is faulty. The code came up Right
front speed sensor, we replaced the speed sensor and the the code does
not go away ?? Anyone have any suggestions or have the same problem??
Thanks for the help in advance.
Just curious... how many speed sensors does the e39 have? I thought there
was just one near the right rear wheel...
Also, the speed sensor is integrated with the ABS module, so you replaced
the whole module, right?
4 - one for each wheel.
I suspect you have no idea how ABS/DSC works right? It compares wheel
speeds. If it finds one wheel turning when other are slipping and the
brakes are in use - it modulates the slipping ones using ABS. If it
determines one of the rear wheels is turning faster than the other
wheels in the car - it knows that wheel is slipping and it reduces speed
on that wheel (with the throttle and brakes.) On later models it gets
even more powerful, comparing the yaw angle of the car (rotation around
it's axis) the G forces and the turned angle of the steering wheel to
determine if the car is going where the driver wants it to go. If not -
it uses dynamic braking on the wheels - individually - to correct.
It couldn't do this without 4 sensors right?
No it isn't. Wheel speed sensors are located (ta-da!) the wheels.
Not any more - they gave that up with the E34 series.
The ABS sensors are used to determine speed - everything is fed
through the ABS/DSC module - including the signal to the
What the original poster apparently doesn't want to accept
is that the damn modules GO BAD... and give all the symptoms
You can drag a cow to water..
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