Abs Brakes
 

I posted this message yesterday but now can't find it so I'm trying again. I have a Dodge 1994 Ram 2500. My ABS light is on and after pressing on brake pedal a couple of times lose my brakes. I have had my pump replaced at a dodge dealer and they kept my truck for 2 weeks and still can't find the problem....Please help.Now I have not cruise.....problem just keeps getting worse......

You can't find your post because you put it in 1st gen section. Sounds like the speed sensor to me.

If you are totally losing the brakes after pressing the pedal, then check the combination valve. It is located down beside the master cylinder and has a button sticking out of the front. Have someone pump the brakes and watch the little black button on the front of the valve. It should push out when the brakes are applied and then return when they are released. If it does not, you have found the problem either with the combination valve or the master cylinder.

If the problem is your antilock system, you are best served to have the system scanned by a DRB scanner. Although, I have yet to see total brake failure when the antilock faults, as either the front end or the rear end will continue to function.

It is real common for a rear wheel speed sensor to fail, trigger the ABS light, and then get fixed only to find there were two problems. The Combination valve and one of the sensors, or the master cylinder and the combination valve or sensor.

The usual reason for failure of the combination valve or the master cylinder is changing the front brake calipers and then trying to bleed the brakes the old fashioned way by pumping and cracking a bleeder on a wheel cylinder. Either the combination valve is bound, or the rear follower of the master cylinder is scored. It is best to use a commercial power bleeder on these systems, and even yet there are some dealer shops that do not do it correctly.