NEED HELP wheel speed sensor

[pja0416]

2009 Trailblazer 4.2
I replace my Wheel Speed sensor and now have ABS and Stabilitrak lights.

I started to get the ABS activation at low speed. I had noticed while doing the front breaks last fall that someone had replaced the wheel speed sensor and routed the wire wrong and it was rubbing on the tire and worn. So I figured it was the problem. I also had the codes read for a different issue (VVT Solenoid, fixed that) and it showed right WSS. That was the same one that was worn. Well, today I finally changed it. After changing it I got the Service Stabilitrak light. I drove it a bit and it didnt go away, but the ABS activating at slow speed is gone. I thought maybe it was because I had only replaced 1 sensor, so I changed the other one. Put it back together now I have both the ABS and Stabilitrak lights. The 4x4 works, but Stabilitrak and ABS seem like they are not working. What did I do? How do I fix it? Hubs are tight, the appeared clean where the sensor attached.

 

[flyboy2610]

What brand of sensor did you use?

 

[Mooseman]

That is more likely a failing wheel bearing, which the low speed activation usually indicates. Replacing the sensor might have exacerbated it.

 

[pja0416]

What brand of sensor did you use?

Mostplus from Amazon. They had over 200 4 ot 5 star reviews. Last n ight I did consider that maybe because they were an off brand they were not communicating properly

 

[pja0416]

That is more likely a failing wheel bearing, which the low speed activation usually indicates. Replacing the sensor might have exacerbated it.

the bearings are not making any noise and the hub is tight, no wiggle in the least. Also why would I just get the stabilitrak light and abs after replacing one then after replacing the other get the break light light in addition to the others.

 

[mrrsm]

THIS Video covers the definitive method for Testing, Diagnosing and Repairing (Re-Testing) any Low Speed ABS Braking Issue:

Jimmy from "1ROAD" takes us through his ABS Sensor Issue:

If you are fortunate enough to have a GM "GYMKO" Tech 2 Scan Tool or a Professional Scan Tool Equivalent ... Dr. Shock shows "How To Perform an ABS Brake Bleed on a GM Vehicle" that would not hurt to be completed as well:

 

[Schurkey]

When it was my '03 Trailblazer doing that (low-speed activation) it was a failing wheel bearing. Nothing wrong with the sensor or wiring, but the sensor was no longer properly aligned with the internal toothed wheel. Low signal voltage = ABS activation at low speed.

Ran it that way for over a year. Eventually the bearing got noisy, and that's when I replaced it. Problem solved.

 

[TollKeeper]

On these trucks, its slightly more expensive to get the hub/sensor, but well worth it. They come as a complete unit, at least they have so far for me. You living in Michigan, who knows if the large O-Ring in there is still in place, and the condition of that tone ring.

 

[pja0416]

When it was my '03 Trailblazer doing that (low-speed activation) it was a failing wheel bearing. Nothing wrong with the sensor or wiring, but the sensor was no longer properly aligned with the internal toothed wheel. Low signal voltage = ABS activation at low speed.

Ran it that way for over a year. Eventually the bearing got noisy, and that's when I replaced it. Problem solved.

I had a computer code for bad right sensor, and I know there was tire rub that had the wire worn half through.

 

[Schurkey]

I had a computer code for bad right sensor, and I know there was tire rub that had the wire worn half through.

You replaced the damaged sensor/harness. Then you replaced the other one, and had real problems.

Putting new sensors into old hubs is not always successful.

 

[mrrsm]

Check Out what THIS VOP (Video Original Poster) discovered while performing a series of GM Factory ABS Circuit Tests using a DMM-DVOM from around 14:30 onward into this Video. Following a Visual Inspection, the VOP discovered another possible cause of this issue can occur from having Hidden Damaged, Corroded or Broken Wires inside of the ABS Harness. His Diagnostic Actions proved that in this instance, the problem was not caused by having a Bad Bearing inside of the Driver's Side Wheel Hub:

Note that the ABS Harness Paired Wiring hidden inside the Black Ribbed Plastic Protection Shielding requires a particular Number of "Twists-Per-Inch" in order to minimizes picking up Electrical Induction via Environmental Electro-Magnetic Interference. Such EMF "NOISE" can confuse any A/C Wiring Harness Signals if not cancelled out by Twisting the Pairs of Harness Wires.

Normal Driving Dynamics and Excessive Vibrations involving Road Sand and Dirt collecting inside of that Black Shielding via its Horizontal Spiral Slit that CAN eventually allow Friction to Wear Away the Insulation, then Weaken, Work-Harden and Corrode the Thin Copper Wiring inside of the ABS Harness.