ATC & ABS lights came on at the same time

[Tom James]

Just returned from a 1,200 mile trip thru Arizona.  On the return trip in the middle of the desert, the ATC & ABS lights came on and stayed on.  Just checked today after it cooled down and they are still on.  Any Ideas?
2006 Patriot Thunder.
Thanks

[Steve Huber Co-Admin]

Tom,
I suspect the ABS system is malfunctioning and triggering an ATC event which would cause both indicators to illuminate. It follows that as long as the ABS problem exists, the ATC lamp will stay on, rather than go out the first time you apply the brakes after an ATC event occurs. The ABS sensors are located in the wheel hubs on your coach. A good hosing out with water might resolve the issue. Otherwise probably time to take to a good repair shop. See pgs 257-258 and 282-284 of your Owners Manual for more info. The ABS will throw codes but the Owners Manual doesn't list them.
Steve

[Eric Maclean]

Tom
Your traction control system and your ABS system both use the ABS wheel speed sensors for wheel speed reference.
A bad sensor , broken wire or too wide of sensor to tone ring gap can cause a sensor to drop out or not send a speed reference signal to the ABS and traction control systems resulting in a failure of the system and related trouble shooting code.
9 times out of 10 the problem is as simple as the air gap between the sensor and a tone ring on one of the wheel speed sensors.
These sensors are slid into a housing at each axle just behind the hub they are only held by a friction clip and can move back away from the tone ring if the wheel bearings are out of adjustment .
It is a common failure to have the sensor moved back far enough to lose signal .

The fastest way to diagnose the ABS system is with a scan tool to retrieve codes and diag the codes .
How ever if you are mechanically inclined and can support the coach enough to safely go underneath you can locate each of the sensors and gently tap them back into place until they contact there prospective tone ring ( no need too worry about the air gap as they self adjust with wheel rotation on initial installation.
While you there check for broken or damaged wires.
The most common sensors to go out of adjustment are the tag axle because of the extra sideways stress put on the wheel bearings when making tight turns that would be my first set to check .

Once the air gaps are all back within spec and each sensor is producing a signal to the controller the controller should recognize the signal and you ABS and Traction control lights should go out this usually takes less than a mile of driving.

Below is a link to a video the should help.

https://youtu.be/iOOzyZH1oOI

Hope this helps
Eric