My ABS and brake light come on tonight in my 99 diesel 3500 4x4.. Anybody here have that problem before or know what the problem or problems could be. Any help would be appreciated. Thanks, Brett

typically it is s the speed sensor in the rear axle.
Parts stores or Mopar have them in stock.
try pulling the battery cables for a few minutes and resetting the code. to see if that clears it.

Also to along with what sthemi said, at some point on those trucks, (can't remember if it's early years or later years), but some of them have a short pigtail harness that went from the chassis to the speed sensor in the rear that would get corrosion in it and set the light off. Check to see if you have this jumper harness, because if you do, I would be inclined to replace this first over the speed sensor.

Pull codes.Unless you do you are just guessing as to the problem.Hard codes will not be erased by pulling the batt cables.Ive seen people at the shop who spent a bundle so they didnt have to pay for a diag.Most times it was cheaper to fix than what they spent.Look for leaks in the system also.Rocky

It was the speed sensor... Wanted to thank you guys for the help.

Speed sensor or tone ring sensor?

Just curious. The newest I own is a 93 and the speed sensor is still in the trans or t-case. Rear has a tone ring sensor on mine.

I just removed my tone ring sensors, and removed the ABS light on the dash. Fixed that issue!

It was the speed sensor on top rear housing.