ABS Trailer Brake Idiot Light... 2008 ProStar

[Waterloo]

I have had the trailer checked, along with the pigtail... Problem is in the tractor, had two shops check the trailer. And we all know about the compass module. I touch the brakes, ABS Trailer light on dash lights up. I replaced all of the fuses, is there a relay somewhere I do not know about, or a wiring fix? I read somewhere about these ABS systems and the wireing at the back of the cab where the pigtail plugs in but cannot find the website I read about this issue. The trailer I pull is a 2011 and in very good condition. Any help appreciated.

[in2trux]

Does the trailer ABS tell tail stay on, or only on brake application?
I had a similar problem with my 8600, trailer ABS would light on the cluster when hammering hard bumps sometimes. Everything checked out fine.
Only thing I could come up with was it was one of the wheel sensor position at the time.

[Waterloo]

(10-20-2016 )in2trux Wrote:  Does the trailer ABS tell tail stay on, or only on brake application?
I had a similar problem with my 8600, trailer ABS would light on the cluster when hammering hard bumps sometimes. Everything checked out fine.
Only thing I could come up with was it was one of the wheel sensor position at the time.

Just when applying the brakes, it is hit and miss... A light foot, no light, heavy, not a panic stop, just hard application like on a short get off ramp and she lights up, along with the trailer ABS light in the rear view mirror.

[Nilao]

Loose wheel bearings causing it to loose sensor to tone wheel signal upon brake application?

[in2trux]

(10-20-2016 )Waterloo Wrote:  

(10-20-2016 )in2trux Wrote:  Does the trailer ABS tell tail stay on, or only on brake application?
I had a similar problem with my 8600, trailer ABS would light on the cluster when hammering hard bumps sometimes. Everything checked out fine.
Only thing I could come up with was it was one of the wheel sensor position at the time.

Just when applying the brakes, it is hit and miss... A light foot, no light, heavy, not a panic stop, just hard application like on a short get off ramp and she lights up, along with the trailer ABS light in the rear view mirror.

It could be something in the trailer wiring. Worst case, the trailer abs doesn't work.
Remember when we didn't have ABS? I think we'll survive.

Does the trailer abs exterior light up, self check when you key on?
That's what DOT looks for.
As long as that self checks, run it and keep drilling.
I make every effort to run it as designed, to a point.

[preacherboy24]

Had the same problem. The ABS wasnt getting the power from the right source and the brake light circuit was powering up the abs.... weird. It was a problem in the trailer harness. I have heard there was a trailer manufacture that routed the harness wrong in the 5th wheel plate area. It was rubbing an area that needed a grommet. My problem was harness rot in the rear of the trailer. It would only happen if I ran through snow and had snow buildup on the harness pulling it down.

[Dcolumbia]

If you are getting the light to light up at braking that usually means the only time it is getting power to the ABS controller on the trailer is when the brakes are applied. Usually the ABS fuse in the dash is bad or the ABS wire in the pigtail is bad. Make sure you have constant power when the truck key is on at the pigtail plug from the truck, no lights on, on at least one wire, the brake light power acts as a backup power wire to the ABS controller if the fuse or pigtail wire isn't making connection. My Volvo did this before, ABS light only works when the brakes were applied enough to trigger brake lights.

[Waterloo]

(10-20-2016 )Dcolumbia Wrote:  If you are getting the light to light up at braking that usually means the only time it is getting power to the ABS controller on the trailer is when the brakes are applied. Usually the ABS fuse in the dash is bad or the ABS wire in the pigtail is bad. Make sure you have constant power when the truck key is on at the pigtail plug from the truck, no lights on, on at least one wire, the brake light power acts as a backup power wire to the ABS controller if the fuse or pigtail wire isn't making connection. My Volvo did this before, ABS light only works when the brakes were applied enough to trigger brake lights.

That is what I read about, the ABS wire having constant power at the pigtail. I wish I would have bookmarked that website that went into detail on this. I'll have to check that. Thanks DC, and everyone else that chimed in!

[pj77rm]

2009 pro star and my trailer abs light comes on even when I don't have a trailer hooked up,I've ran every wire. I think it's the abs module I just put a kill switch on it lol