2nd Gen Non-Engine/Transmission Weird ABS issue

[TLadd]

I've got a 2001 Dodge Ram 3500 4x4 Sport Quad Cab Automatic. The ABS and Brake lights are on. The module on top of the ABS pump has just been replaced, because it was causing the pump motor to run constantly. Upon start-up the lights turn off then come back on and stay on til you shut the truck off. I scanned the codes for the dash lights and the scanner said no communication. The scanner would enter all other powertrain components, but not the ABS. The vacuum is good. I'm thinking it's the ABS sensor in the rear end. I talked to one shop and they said it could be the PCM. I've never heard of this and I wouldn't think that the whole PCM would go bad just on an ABS glitch. I'm stumped on this one, any suggestions or leads would be much appreciated, thanks.

 

[DieselDoghouse]

the obvious and possibly irrelevant would be have you done any work that would have disrupted a ground in the ABS system? I have in the past and suffered the same events as you til corrected.

 

[DShore]

I had a similar problem on 1998. 5 CTD, only the cruise control was also involved. I replaced the Power Train Control Module and the CAB (anti-lock brake module). My dealer "refreshed" the software on both the PCM and CAB module. At this point no codes were set. They told me that they had contacted Technical Assistance (STAR) as to why the PCM did not recognize that this vehicle does not have cruise, yet it really does. STAR needs to communicate to the dealer so we can get everything to function. After STAR and the dealer finished, the dash lights and cruise control all work properly... $$$$$$$

 

[THess]

You may have already checked it, but when my early 98 had these problems it turned out to be the pigtail wire that connects into the speed sensor in the back. Try doing a search for wheel speed sensor and there is a post somewhere that tells how to test the actual sensor. I think the resistance is supposed to be something like 1800 ohms across the 2 pins . I hope this helps. Definately test the sensor before you spend $50.

 

[jmy]

Tladd,

A regular scanner will not read the dodge ABS codes.
Even professionl scanners, designed to service ABS systems, will not usually read the Dodge ABS codes correctly.

If you have access to a DRBII or DRBIII as used by the dealer you can access the ABS control unit and retrive the stored codes. Since you replaced a defective controller with another controller and have the ABS light sound like maybe a program mismatch between the old ABS controller and the one you installed.

The ABS controller that you installed should be programmed to match the defective controller that you removed. The numbers on the top of the new controller should match the numbers on top of the old controller if the programming is correct.

At one time dodge only supplied the unprogrammed ABS controller and the dealer had to program.

A DRBII or DRBIII scanner will isolate the problem.

 

[DShore]

Make sure PCM and CAB module numbers on truck are correct. CAB module on my truck was not the correct one. Have a CAB module w/# P52009711AF & # TXXBK1808A4605. Anybody know what it fits?

 

[Missouri Mule]

Check and clean rear wheel sensor connector on the differential. The "abs and brake warning light' will also go on if you have a rear brake light out.

 

[WAHarrison]

I had a similar porblem on my 94, and it was the ground wire for the ABS that had corroded and was not making contact. Check all the grounds on the truck that you can find and that might fix it.

 

[JacobsD]

On my 95 I had the ABS randomly start kicking on at 55 mph or above when I hit the brakes. A yank on the ABS fuse cured that real quick. :-laf



I prefer regular brakes to ABS anyways. A good driver should be able to control his stopping with minimal skidding anways.