Can someone please give me some things to check as to why the ABS light stays on , with my wife's car. When this first happened both the brake light and ABS light stayed on. At this point only the ABS light is on.

 

This happened on my 1999 RAM. It was the sensor on the differential. It started as the two lights on and eventually the speedometer quit working. O'Reilly Auto special ordered the part for me, it was about 40$ I think.

When the sensor goes out, it's unable to determine your speed and therefore unable to tell whether or not the ABS needs to be engaged when you press the brakes.

 

Note! Also check your brake fluid. My ABS and Brake light came on in my 1999 RAM about two weeks ago and Saturday night the brakes went out.

The master cylinder was bone dry. I thought I checked those things regularly so I topped it off and drove around. It seemed fine and the ABS and Brake lights went out. So I parked in the driveway and came out an hour later to find a 2 foot puddle under the tire. The brake cylinder had failed. It was only an 8$ part but I had never done one before. With the help of a neighbor, we got it in and the system was bled. So far the truck is good again!