ABS light
The anti-lock brake system light on my dash comes on occasionally and randomly. It doesn't come on every time I drive. It may not come on for hundreds of miles, like all the way from Sedona to Oregon...
Forum Discussion
Which Chassis do you have? I take it, a Workhorse since you had it looked at by a Chevy dealer... But more important to know which Year/Make/Model of Chassis vs. the Coach to deal with an issue like this. That said, I guessed W22 with 8.1V8. Then tried to at least look up some parts. RockAuto.com shows Workhorse, and their selection for braking was very limited and nothing for electronics. So no joy. A 2002 Ford F53 chassis has a sensor on each front wheel (close to the hub) and one sensor at the top center of the rear axle (above the Ring Gear). Working on our Fords, I've seen dry "dross" clinging to the Front Sensors, and greasy "dross" on the Rear Sensor. This is because the Sensors are mildly magnetic, and the fronts are out in air, while the rear gets axle lube slung onto it.
That "dross" is from wear on the rear and wear along possibly with rust on the front. Normal if it's not excessive, but too much will bother the ABS "brain" and put the Light on. If it was mine, or we were together and I could help you, I'd try to pull the Sensors and be sure they don't have Metallic Stuff clinging to them. Again on Ford, the Sensors are held in place with little 10mm fasteners. The Rear has an O-Ring Seal, and since it's into the Axle Lube, I clean the mounting area with spray brake cleaner before removing it so dirt doesn't fall into the axle.
I don't think the Sensors can be tested with ordinary tools like a Digital Volt Ohm Meter (DVOM). On Ford, I'd risk $10 on the Rear one, but the Fronts are closer to $100 each.
Again on Ford, the ABS does a "self test" every time you start the engine, so I an understand how it might set the light while driving then not light it next time you start up. On one of our Fords, a failed Rear Sensor turned the Light on and off while driving. It also took the Cruise, Speedometer, and Overdrive with it.
That "dross" is from wear on the rear and wear along possibly with rust on the front. Normal if it's not excessive, but too much will bother the ABS "brain" and put the Light on. If it was mine, or we were together and I could help you, I'd try to pull the Sensors and be sure they don't have Metallic Stuff clinging to them. Again on Ford, the Sensors are held in place with little 10mm fasteners. The Rear has an O-Ring Seal, and since it's into the Axle Lube, I clean the mounting area with spray brake cleaner before removing it so dirt doesn't fall into the axle.
I don't think the Sensors can be tested with ordinary tools like a Digital Volt Ohm Meter (DVOM). On Ford, I'd risk $10 on the Rear one, but the Fronts are closer to $100 each.
Again on Ford, the ABS does a "self test" every time you start the engine, so I an understand how it might set the light while driving then not light it next time you start up. On one of our Fords, a failed Rear Sensor turned the Light on and off while driving. It also took the Cruise, Speedometer, and Overdrive with it.
