GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

    Caution: Unless directed otherwise, the ignition and start switch must be in the OFF or LOCK position, and all electrical loads must be OFF before servicing any electrical component. Disconnect the negative battery cable to prevent an electrical spark should a tool or equipment come in contact with an exposed electrical terminal. Failure to follow these precautions may result in personal injury and/or damage to the vehicle or its components.

  1. Remove the negative battery cable.

  2. Object Number: 379478  Size: SH

    Important: The area around the electric hydraulic control unit (EHCU) MUST be free from loose dirt to prevent contamination of disassembled ABS components.

  3. Thoroughly wash all contaminants from around the EHCU.
  4. Disconnect the three electrical harness connectors from the electronic brake control module (EBCM).
  5. Important: Make sure that brake lines are tagged and kept in order for proper reassembly.

  6. Disconnect the 5 brake lines from the brake pressure modulator valve (BPMV). When looking at the brake pipe port face of the BPMV, the ports are assigned as follows:
  7. • Upper Left--Left Front Output
    • Upper Middle--Right Front Output
    • Upper Right--Rear Output
    • Lower Left--Master Cylinder Secondary/Front Input
    • Lower Right--Master Cylinder Primary/Front Input
  8. Remove the 3 bolts (4) securing the EHCU mounting bracket (3) to the frame rail (5).
  9. Remove the EHCU (1) from the vehicle.

  10. Object Number: 379484  Size: SH
  11. Remove the 2 bolts (4) securing the BPMV mounting bracket (3) to the BPMV (1).
  12. Disconnect the 2 way ABS pump motor connector.
  13. Remove the four T-25 TORX® bolts from the EBCM (2).
  14. Important: 

       • Do not use a tool to pry the EBCM or the BPMV. Excessive force will damage the EBCM.
       • Do not reuse the EBCM mounting bolts. Always install NEW bolts.

  15. Remove the EBCM (2) from the BPMV (1). Removal may require a light amount of force.
  16. Clean the EBCM to BPMV mounting surfaces with a clean cloth.

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 379484  Size: SH

    Important: Do not use RTV or any other type of sealant on the EBCM gasket or mating surfaces.

    Important: Do not reuse the old mounting bolts. Always install NEW bolts with the new BPMV.

  1. Install the EBCM (2) onto the BPMV (1).
  2. Install the four EBCM bolts.
  3. Tighten
    Tighten the four bolts to 5 N·m (39 lb in) in an X-pattern.

  4. Connect the 2 way ABS pump motor connector to the EBCM.
  5. Install the BPMV (1) to BPMV bracket (3).
  6. Install the BPMV to bracket retaining bolts (4).
  7. Tighten
    Tighten the bolts to 9 N·m (7 lb ft).


    Object Number: 379478  Size: SH
  8. Install the EHCU (1, 2) to the vehicle frame (5).
  9. Tighten
    Tighten the three EHCU bracket bolts (4) to 25 N·m (18 lb ft).

  10. Connect the two electrical harness connectors to the EBCM (1).
  11. Important: The brake pipes are held in the proper place by a frame mounted plastic bracket. Ensure the brake pipes stay in the correct place for proper reassembly.

  12. Install the 5 brake pipes to the BPMV (6).
  13. Tighten
    Tighten the brake pipe fittings to 30 N·m (22 lb ft).

  14. Connect the negative battery cable.
  15. Bleed the brake system. Refer to Antilock Brake System Automated Bleed Procedure .
  16. Return to Diagnostic Starting Point .