Need a little help here as I am stumped. I just pulled the Vac/steering pump as a unit and fixed the oil leak with new seals and a new power steering pump. After everything was back in and fluids were topped off I test drove it and right away the ABS and parking brake light came on. I checked the vac line and its connected. My vent control works great so I know the system has vacuum. Test drove it and power steering works and brake pedal feels good but a panic stop locks up the rear brakes (no abs function). What am I missing?

 

Truck is a 2001 2500 Cummins 4x4 extended cab.

 

found a wheel sensor plug was not properly connected.

 

 

Thx in advance.

Edited August 5, 20186 yr by SavageConcepts

You must have disturbed something in the wiring when doing the reseal.   Take a good look at the brake pressure switch at the combination valve.   

RWAL or 4 wheel ABS?

On 8/5/2018 at 5:56 PM, SavageConcepts said:

I checked the vac line and its connected. My vent control works great so I know the system has vacuum. Test drove it and power steering works and brake pedal feels good but a panic stop locks up the rear brakes (no abs function). What am I missing?

I am curious about this statement. Does the ABS system rely on vacuum pressure in some way? As long as I have owned the truck, the ABS has been non-functioning. The ABS module is currently disconnected as when you plug in the pig-tail there is a motor that runs constantly. I have had many vacuum related issues over the years, so i am wondering if there could be a vacuum related problem. I assume that my issue is a bad control board, just never have done anything about it. 

1 minute ago, adamey1000 said:

Does the ABS system rely on vacuum pressure in some way?

 

Neither. Only relies on the 3 speed sensors if braking is normal then all 3 sensors will slow together. But like in a panic stop on slick road one wheel will slide then the speed on that wheel will be greatly lower so the ABS system back pumps the pedal prevent any further pressure applied till the speeds equalize again. 

3 minutes ago, adamey1000 said:

The ABS module is currently disconnected as when you plug in the pig-tail there is a motor that runs constantly.

You need to send in your ABS module to Module Masters in Moscow, ID they can rebuild that module and fix that problem.

2 minutes ago, Mopar1973Man said:

You need to send in your ABS module to Module Masters in Moscow, ID they can rebuild that module and fix that problem

Its been on my list for awhile now, just havent gotten it done yet. i think i have his site saved around here somewhere. 

Why wait... You can still drive without the module just the speedometer doesn't work. Also you'll need to unhook your grid heater the since there is no speed it won't cancel the grid heater at 25 MPH like typically.

 

https://modulemaster.com/rebuilds/shop/brakes/abs-modules/abs-kh-dodge/

40 minutes ago, Mopar1973Man said:

You can still drive without the module just the speedometer doesn't work

If the module is disconnected now, why wouldn't i have lost speedo already?

Because there is an internal issue of the module most likely and the speed information isn't passing to the CCD bus to be received by the ECM, PCM and Cluster.