The Ultimate ABS Control Module Repair Guide

The following is an ABS control module repair guide on:

2000 to 2006 Chevy Suburban, Tahoe, Silverado, GMC Yukon and Cadillac Escalade 

The ABS (antilock brake skid) controller or computer is responsible for limiting the brake line pressure which allows a wheel or wheels that have locked up to start rotating under severe braking conditions which helps keep the vehicle under control in a hard braking or skid event. Every vehicle equipped with an this system has a computer module controller that can go bad as parts sometimes do which casus the ABS warning light to be on.

Please follow this video and article to determine if your module has failed by process of elimination.

Also See: ABS Warning Light On Repair

Watch the video below then continue with the guide to gain additional tips and updated information

Begin Repair Guide

Most ABS diagnostic codes can be access by the ALDL connector much like the engine control system, but this takes a specialized code scanner with the capability to read such codes. If the vehicle is equipped with a traction control system it uses a different ABS computer which are not interchangeable with non-traction controlled vehicles.

When this module fails it can do so in a few different ways one of the most common problems is the control relay that is built into the unit to fail either by not closing which delivers electrical power to the computer circuitry, or the relay will not disengage which leaves the unit on even with the ignition key off, which will drain the battery down.

This relay is internal inside the controller, but I have heard of people opening them up and just replacing the relay though it takes some soldering on the circuit board. If you do not feel comfortable doing this simply get a replacement factory replacement you can get them from Amazon for about $190.00. The dealer or repair garage will charge about $450 to $550 for the same job (parts and labor).

The unit can fail because one of the control valve activation coils has burned out which leaves only three out of the four wheels to be controlled hence the light being on. The computer control module appearances may vary, but follow the same steps. This article pertains to many Chevy trucks and SUV's, this particular repair was done on a Chevy Tahoe.Before we begin, you will need to locate the module which is usually under the vehicle or in the engine compartment. If it's not located in the engine compartment it will be under the vehicle on the frame rail on the driver’s side, this location is used mostly on trucks and SUV's. If it is in this location you will need a jack to lift up the vehicle to get to it.

Replacing the module is not too difficult and should take you about an hour, are you ready to change your own part and save some cash? Begin the repair by parking your vehicle on level ground with the transmission in park and the emergency brake set. Remove the battery cable from the negative terminal of the battery. Lets get started!

Tools and supplies you will need:

  • Replacement ABS brake control module assembly
  • Socket set including Torx bits
  • Wrench set
  • Screw driver set
  • Shop towels
  • Protective eye wear and gloves

Step 1

Once the module is located and with negative battery cable disconnected, release the electrical connectors from the unit by pushing the connector’s safety using a small screwdriver. One connector will be for the main power and ground for the unit while the opposing connector will be sensor inputs and data bus wiring to the main ECM computer that controls the warning light itself.

The weather packing can make it a little difficult to remove sometimes so wiggle the connectors as you gently pull on them to remove.

Disconnecting Electrical Connectors

Step 2

After removing the electrical connectors, it's time to remove the controller mounting bolts which will probably be four Torx head bolts that can be little tough to get to if the module is under the vehicle like this one is, use 1/4 inch drive tools because they are smaller and easier to maneuver. This operation is much easier when the controller is under the hood.

Removing ABS Computer Controller Mounting Bolts

Step 3

Make sure the controller is clean and dry and then gently remove it by lifting straight up from the valve assembly. It might be a little stuck because of the weather seal so use a small screwdriver to gently pry and separate to help remove it. At this point it sometimes can pop up so keep your hands on it.

Removing The Module

Step 4

After the failed unit has been removed, match the old part to the new replacement unit, they should be an identical match. Be sure to count the number of electrical pins in each connector because there are minor variations according to what options and SUV, can or truck may have such as anti-skid options.

New Controller

Step 5

Next, be sure the pump motor is clean and free from dirt before installing the new unit, install the new to the mounting surfaces and ensure it sits flush and seals completely onto the valve solenoid assembly. This can take some extra effort because the valve stems need to fit through the module.

Installing New Control Module

Step 6

After the unit is securely in place, reinstall the mounting bolts and tighten in an "X" pattern to mount the unit squarely into the pump and valve, this will ensure the proper operation of the coils over the valve cores.

Mounting Bolt Tighten Pattern

Step 7

Once all the mounting bolts are tight, reconnect the electrical connectors back onto the valve assembly and make sure the connectors are clean from dirt and grime and recheck your work.

Reconnect the battery negative cable and start the car, the warning light will go off shortly after the engine is running or after you have driven the car for a short time. 

No code clearing is required in most cases for American built vehicles, but some older European and Japanese models may need to be cleared using a scanner, a local garage or auto parts tore can do this for you.

Reconnecting Electrical Connectors
If you have any question concerning this repair please visit our forum where hundreds of ABS controller module questions have already been answered.  
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