Traction active, WSS and Service Stability

[easterr]

Hi All,

I hope someone may be able to shed some light on this issue.

2006 Denali had service stability and ABS lights on and traction control would activate. Mechanic found the drivers front ABS sensor had a broken wire. Replaced the sensor, confirmed the ring in the hub looks good and now the traction control activates when starting from a full stop.

This happened previously and the front hub needed to be replaced 3 years ago. Mechanic said all sensors are functioning fine according to the scanner - no fluctuation in the scanner numbers, so he says it must be another issue. Seems very coincidental. I should also mention we have an intermittent flat tire sound when driving but tires are not flat. I have read, to my surprise, this could indicate a bad hub/bearing.

I suspect a wheel bearing but if it's removed to check, I am told it should be replaced, so it's a $400 gamble. My question is, if the wheel speed sensor is causing this issue, will that register on the scanner? Or does the scanner just check how the sensor is functioning. In other words, will the output read by the scanner change if the sensor identifies wheel spin and activates traction control?

Thank you in advance

 

[easterr]

I picked up the Denali and the traction active happens most of the time when starting from a stop. Mechanic said all sensors appear to be working as they should be per his scanner - even when driving. There are no other codes - ABS or otherwise. I did not ride with the mechanic, but when the traction active engages, assuming it's due to a speed sensor, would the different MPH show on thew scanner?

I've continued to research and 2 other reasons could be the EBCM or steering position sensor. Anyone know of tests to check these? I will turn off the stability control so the traction control doesn't engage, but sure would like to resolve this. Thank you

 

[easterr]

Hi All,

Follow up to the above. I bought a scanner that displays the speed of the wheel sensors. They are all functioning and no one specific sensor seems to be an issue. When the traction control activates, the sensors do report different speeds, however, it varies from sensor to sensor. In other words, it does not appear to always be the left front, for example, although, it was more common with that the left front was the different speed, and that is the sensor that was just replaced. I have no experience with this, should all sensors report the same speed at all times, or will speeds vary and may not cause traction control to activate? Or is this an indication there could be something other than a WSS causing this? Thank you in advance.