GM Service Manual Online
For 1990-2009 cars only

Caution: Refer to Brake Fluid Irritant Caution in the Preface section.

Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in the Preface section.

Removal Procedure

Caution: For safety reasons, the brake pressure modulator valve assembly must not be repaired, the complete unit must be replaced. With the exception of the EBCM, no screws on the brake pressure modulator valve assembly may be loosened. If screws are loosened, it will not be possible to get the brake circuits leak-tight and personal injury may result.


    Object Number: 458835  Size: SH
  1. Turn OFF the ignition.
  2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Remove the left front wheel. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  4. Remove the left front fascia extension. Refer to Front Bumper Fascia Extension Replacement in Bumpers.
  5. Remove the front air deflector. Refer to Front Air Deflector Replacement in Body Front End.
  6. Important: The area around the electronic brake control module (EBCM)/ brake pressure modulator valve (BPMV) must be free from loose dirt to prevent contamination of disassembled antilock brake system (ABS) components.

  7. Thoroughly wash all contaminants from and around the EBCM/BPMV.
  8. Disconnect the EBCM connector position assurance (2) from the EBCM electrical connector (1).
  9. Rotate the EBCM connector tab up to the unlocked position.
  10. Notice: To prevent equipment damage, never connect or disconnect the wiring harness connection from the EBCM with the ignition switch in the ON position.

  11. Disconnect the EBCM electrical connector (1) from the EBCM (4).
  12. Caution: Brake fluid may irritate eyes and skin. In case of contact, take the following actions:

       • Eye contact--rinse thoroughly with water.
       • Skin contact--wash with soap and water.
       • If ingested--consult a physician immediately.

    Notice: When removing the brake pressure modulator valve, protect the vehicle exterior from possible brake fluid spillage. Brake fluid can cause damage to painted surfaces.

    Notice: Excessive bending of brake pipes during BPMV removal or installation may cause permanent damage that will require replacement.


    Object Number: 458848  Size: SH

    Important: Record the location of all brake pipes to the BPMV for use as an aid during installation.

  13. Remove the 2 master cylinder brake pipes (1) from the BPMV (2).

  14. Object Number: 458850  Size: SH
  15. Remove the 4 wheel brake pipes (1) from the BPMV (2).

  16. Object Number: 458866  Size: SH
  17. Clean any brake fluid spillage from the BPMV (1).
  18. Remove the 2 BPMV bracket nuts (2).
  19. Remove the EBCM/BPMV assembly (1) from the BPMV bracket (3).

  20. Object Number: 458842  Size: SH
  21. Disconnect the BPMV electrical connector (2) from the EBCM (3).

  22. Object Number: 458840  Size: SH
  23. Remove the 6 EBCM to BPMV screws (2).

  24. Object Number: 458834  Size: SH
  25. Clean the surface of the EBCM/BPMV assembly.
  26. Important: The EBCM cannot be repaired. If faulty, the unit must be replaced.

  27. Separate the EBCM (2) from the BPMV (1).

Installation Procedure


    Object Number: 458834  Size: SH
  1. Clean the seal surface of the BPMV.
  2. Install the EBCM (2) to the BPMV (1).

  3. Object Number: 458840  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  4. Install the 6 EBCM to BPMV screws (2).
  5. Tighten
    Tighten the 6 screws to 3.2 N·m (28 lb in).


    Object Number: 458842  Size: SH
  6. Connect the BPMV electrical connector (2) to the EBCM (3).

  7. Object Number: 458866  Size: SH

    Important: Make sure that all 3 rubber isolators are installed on the BPMV. The isolators protect the EBCM/BPMV assembly from vehicle vibrations.

  8. Install the EBCM/BPMV assembly (1) to the BPMV bracket (3).
  9. Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  10. Install the 2 BPMV bracket nuts (2).
  11. Tighten
    Tighten the 2 nuts to 10 N·m (89 lb in).

    Caution:  The brake pipes must be fully installed to the brake pipe mounting retainers on the frame. Failure to properly retain the brake pipes may cause the pipes to contact the frame and/or the transmission resulting in possible loss of brake fluid and personal injury.


    Object Number: 458850  Size: SH

    Caution: Make sure brake pipes are correctly connected to BPMV. If brake pipes are switched by mistake Inlet vs. Outlet, wheel lockup will occur and personal injury may result.

    Important: If a new BPMV is being installed, remove the shipping plugs from the valve openings.

  12. Install the 4 wheel brake pipes (1) to the BPMV (2) using the locations recorded during the removal procedure.
  13. Tighten
    Tighten the 4 brake pipes to 15 N·m (11 lb ft).


    Object Number: 458848  Size: SH
  14. Install the 2 master cylinder brake pipes (1) to the BPMV (2) using the locations recorded during the removal procedure.
  15. Tighten
    Tighten the 2 brake pipes to 15 N·m (11 lb ft).


    Object Number: 458835  Size: SH

    Notice: To prevent equipment damage, never connect or disconnect the wiring harness connection from the EBCM with the ignition switch in the ON position.

  16. Connect the EBCM electrical connector (1) to the EBCM (4).
  17. Rotate the EBCM connector tab (2) down to the locked position.

  18. Object Number: 458843  Size: SH
  19. Install the EBCM connector position assurance (2) to the EBCM electrical connector (1).
  20. Install the left front fascia extension. Refer to Front Bumper Fascia Extension Replacement in Bumpers.
  21. Install the front air deflector. Refer to Front Air Deflector Replacement in Body Front End.
  22. Install the left front wheel. Refer to Tire and Wheel Removal and Installation in Tires and Wheels.
  23. Lower the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  24. Perform the Auto Bleed Procedure. Refer to Antilock Brake System Automated Bleed Procedure .
  25. Perform the ABS Diagnostic System Check. Refer to Diagnostic System Check - Vehicle in Vehicle DTC Information.