shorted, or broken circuit?

[muddy12]

In the process of tracking down a wheel speed sensor issue. I have it down to the wiring for the right rear sensor, and I'm 99% sure it's an issue with the wiring harness.
Using JScan, I've been keeping an eye on the speed sensor outputs. they will all read the same MPH for a bit, then the right rear will jump to some crazy high RPM, which is what trips the ABS, traction control, and service 4x4 lights.

Does anyone have any experience with these speed sensors? would it be a break in the wire, or a short in the wire, that would cause the reading to spike? trying to figure out if I need to be looking for broken/almost broken wires, or if a contaminated/dirty plug is more likely.

Truck is a 2012 by the way.

Thanks,
muddy

 

[CVX20]

I've seen that on front hub bearings and I think what causes it there is slop in the bearing that damages the teeth on the reluctor wheel and/ or metal particle contamination.It'll kick on the traction control because it thinks that wheel is spinning.There is no reference voltage to these sensors as they are just an AC Voltage generator so really the only way to make them read high is for there to be a perceived excess of teeth on that wheel.I would pull the sensor and inspect the reluctor wheel.

Sensors will read low on a scan tool whether it's a short or and open in the circuit.

 

[muddy12]

well, crap!!!

all 4 wheel speed sensors are new. (replaced them around Christmas, before I had a scanner capable of reading outputs)

guess I can check the reluctor, again, but I had that wheel off a couple weeks ago, and it all looked fine.

 

[muddy12]

pulled the wheel and rotor off of the rear right again last night. Teeth on the reluctor all look fine, and there was no contamination (metal/debris) of any kind between any of the teeth.
just for $*!#$ and giggles, I pulled the sensor, and took a wire brush to the back side of the backing plate (where the sensor mounts). Made the 18 mile drive to work this morning without issue, but I'm not holding my breath as it seems totally random as to when the warning lights come on.