Best way to make sure the ABS light is working correctly?

Not @Rideandrepair, but that's not normal. Usually if the light comes on when you hit the brakes, you have no ABS 12V supply.

Does the light come on when you key on, or can you hear the modulators click when you plug in the pigtail?

 

Been 3k miles away from my truck and trailer for the last 3 weeks so I’ll check it out when we’re reunited.

I had a feeling that something wasn’t right. Trailer is a 2022 and I had the abs light stuck on after driving through deep water on I-5 in CA during a flooding rain storm.

Was stuck on for a couple months before it went out again. The day it went out was another day of driving in the rain. I just figured that mud from the storm in CA screwed up a sensor and it had eventually fixed itself.

Going to get it looked at by the dealer now since it has other issues going on now also.

Maybe just take a small loss on it and trade it in on a new one.

 

That could be normal, if your truck is old enough that it doesn't have a 12v center pin in your trailer pigtail (I think pretty much all trucks have the hot center pin after around the year 2000). If your truck is a newer truck, for some reason your aren't getting a 12v power supply to your ABS. Could be either in your truck or your trailer.

 

Good point, all trucks post 97 should have it.

 

That usually means a blown fuse. The pigtail center pin should always be hot when the key is on so that's a quick way to check. The ABS system will draw power from either the center pin or, as a backup, from the brake light circuit.

 

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