Well it appears like my brakes are going to need some work. Not the normal pads / rotors work. The ABS has been activating the last couple of days. No, I wasn't stopping hard, and no, the roads aren't slick. There was no reason for the system to activate.

Basically, some times when coming to a stop the ABS system will come on. Not always, and I haven't seen any correlation between things I'm doing and when it activates. It's 90 degrees here, and dry.

Any thoughts?

 

I would first ask if you have a scanguage unit or code reader to see if the vehicle is throwing any codes. Then someone else with more knowledge than me needs to help out.

 

There is another thread on this forum that mentions similar ABS activation behavior where the exciter ring on one of the axle shafts was cracked/damaged. This would cause the sensor to misread wheel movement and think the tire was not rotating (read:sliding) and thus cause the ABS activity. It's possible that you have the same/similar issue.

 

I don't have a scanguage, but can try to pull codes. My car hasn't complained to me though. No lights.

And thanks! I tried searching this forum for abs info, and found it very difficult to find anything. The exciter ring info sounds exactly like my problem.

I'll definitely post with any conclusion.

 

As I was stopping the car would kind of lurch forward (not violently). Usually occompanied by a quick clunking noise of some kind. It did it in all conditions, but not every time. Turned out to be the Exciter ring. Paid $360.08 to get it fixed.

 

I had a similar problem and was reminded that perhaps that's just how the brakes on a hybrid could be... maybe I wasn't describing the situation accurately enough.

Turned out to be TWO broken exciter rings (or "ABS Sensor" rings, as it said on the workorder). Eventually got bad enough that I got into warning messages like "4x4 Locked", "4x4 Temporarily Disabled," "Service 4x4" and "Service Brake System." Exactly the same symptoms as OP and eaglefan89.