ABS light .

[Oh-one]

While in the smoky mtns. I was using the engine brake to slow the MH decent down the hills. After a while the ABS light came on. The engine brake worked fine and Mh never got too fast. In fact I did not need to use the foot brake until we had to stop at a traffic light. Why did the ABS light come on? Afterwards the light went out and back to normal. We have a 07 HR Imperial with 400 ISL and two stage engine brake. Thanks Sam

[Gary RVRoamer]

The ABS light indicates there is a problem in the antilock system, unrelated to the engine brake. Typically the problem will be in a wheel sensor and I suspect that the ABS computer lost contact with one of the wheel sensors and so turned on its error light, then later the problem cleared up and the error got reset.

[Oh-one]

I understand the ABS system, but it came on when the trans. temps were high due to a long downhill grade with all engine brakes on for extended time. I guessed that the system might eliminate the ABS for a time until the temps went down. ie: In a severe braking situation you could lock em up if you needed to. This is the only time the ABS has ever lit up. If I had a bad sensor, why do I not have more instances of ABS lighting up?

[Gary RVRoamer]

In a severe braking situation you don't want to "lock em up", so I doubt if they would intentionally turn off the ABS.

The ABS wheel speed sensors are active all the time. I'm wondering if you also have an anti-skid or track stability system that uses the same sensors. The Monaco/HR coaches often have that sort of thing cause it is fairly easy to add once you have the ABS wheel speed sensors in place.