2010 Cascadia, ABS Light ON

I think the abs module is separate from the ecm, so it might not store a code in the Ecm. The abs light probably came on due to the wheel spin, and it's usually a wheel speed sensor fault or the sensor is dirty. Sometimes it will pop on if the speedometer is registering a different speed than the sensor and tone ring. If the truck is driving normally it won't mess anything up, but it could be a problem on an inspection if they check your dash when you cycle the key, though they usually only care about the trailer abs light.

 

To clarify, when you cycle the key the truck and trailer abs lights are supposed to come on and test on the dash for about three seconds, contingent on you being hooked to a trailer. If bob tailing, it's only supposed to show the truck testing when you turn the key .

 

Grumppy, I assumed it was the tractor abs according to his original post. If it's the trailer abs, the same still applies, typically a dirty speed sensor or broken wire to a sensor. If it comes on when applying the trailer brakes, he should test the pig tail center pin and see if it has constant voltage, if not check the 40 amp fuse for trailer abs and replace if bad.

 

If it's an automatic, then it's probably some kind of self protect mode that limits torque output when it senses a wheel slip so it doesn't mess up the axles or output shaft. We had volvos that would have the abs light on and the tics light on, it was always he wheel speed sensor down by the axle that was bad, or the speedometer was off. Either way someone can plug into your abs module and see which sensor is bad, or you could take them loose and spray cleaner in them to see if it's keeping the signal from being sent. It's not a safety concern, it's merely an issue if the wrong high strung DOT cop stops you.

 

This respond will probably be useless but..
I had similar situation. Had TA check it hoping it will be something easy, but no. No communication between something and something. Take it to the dealer. Before I got home I've fixed it myself.
There is a fuse box in engine compartment. Driver side, not to far from dipstick. When I was checking oil I've noticed that it was really loose. Lousy design. I've wedged something underneath to stop it from shaking and made sure that fuses and relay inside were tight. My abs light disappeared. It still comes on when I start engine for few seconds as it should. It might be just coincidence, but I had no problem since then.