chakka

As many have this issue, I'd like to know what I need to be looking for/at on figuring out my light coming on.
My light comes on once the car gets over 5-7mph. I've starting looking at the wheel sensors, but beyond the obvious of a broken wire(which I've not found), what should I be looking for or measuring(voltage/ohm)? The casing on the rears basically disintegrated as I unplugged the wire, so I'll need to address that, but the wires and plugs look good. I'm reluctant to remove the sensor, as many have noted due to age the sensor cap can break off, so I'm reluctant to remove, unless I need to. My question is, what do I need to do to try to determine which wheel sensor is bad?

Mrmerlin

at this point its prudent to remove the wheel sensors and clean them, also check the signal rings
use DC111 on reassembly so they dont corrode.
use a multi meter to check for continuity of the wire through each sensor.
usually a broken ground wire near a sensor will be found

davek9

Unplug the connector at the ABS controller, there are 4 pins in it that are the connections for each wheel, put a scope on each pin and spin the wheel, you will get a wave form.
If you don't have access to a scope, use an old volt meter non digital, set it for low voltage reading and watch the needle move when the wheel is turned.
This will at least point you to which sensor or wire leading to the ABS controller has a bad connection, if all 4 give you a reading, swap controller.

Dave K

Note: the manual has the pin-outs and IIRC the troubleshooting procedure

GregBBRD

Hook up the Factory Bosch tester, run through the initial sitting still tests, and go drive the car.
Replace the bad component.

One week tool rental = $200 plus shipping.