GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Astro - 4WD 🢒 Brakes 🢒 Hydraulic Brakes 🢒 Brake Pressure Modulator Valve Replacement

Removal Procedure

    Object Number: 556742 Size: SH
  1. Remove the fuel pipe shield (3) from the frame bracket (2) by removing the 2 nuts (4).

    2. Important: Thoroughly wash all contaminants from around the EHCU (1). The area around the EHCU (1) MUST be free from loose dirt to prevent contamination of disassembled ABS components.

  2. Disconnect the 2 electrical harness connectors from the electronic brake control module (EBCM).

    3. Important: Make sure that brake lines are tagged and kept in order for proper reassembly.

  3. Disconnect 5 brake lines from the brake pressure modulator valve (BPMV).
  4. Slide the EHCU (1) off of the frame bracket (2).

    5. Object Number: 556746 Size: SH
  5. Remove 2 bolts (4) securing the BPMV mounting bracket (3) to the BPMV (5).
  6. Disconnect the 2-way ABS pump motor connector.
  7. Remove the 4 T-25 Torx® bolts (1) from the EBCM (2).

    8. Important: Do not use a tool to pry the EBCM or the BPMV. Excessive force will damage the EBCM.

  8. Remove the EBCM (2) from the BPMV (5). Removal may require a light amount of force.

    9. Important: Do not reuse the EBCM mounting bolts. Always install new bolts.

  9. Clean the EBCM to BPMV mounting surfaces with a clean cloth.

Installation Procedure

    Object Number: 556746 Size: SH

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

  1. Install EBCM (2) onto BPMV (5).

    2. 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.

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

  2. Install the 4 EBCM bolts (1).

    3. Tighten
    Tighten the 4 bolts to 5 N·m (39 lb in) in an X-pattern.

  3. Connect the 2-way ABS pump motor connector to the EBCM.
  4. Install the BPMV (5) to the BPMV mounting bracket (3) with the 2 bolts (4).

    5. Object Number: 556742 Size: SH
  5. Slide the EHCU (1) back onto the frame bracket (2).

    6. Important: The brake pipes are held in the proper place by a frame mounted plastic bracket. Make sure that the brake pipes stay in the correct place for proper reassembly.

  6. Install the 5 brake pipes to the EHCU (1).

    7. Tighten
    Tighten the brake pipe fittings to 30 N·m (22 lb ft).

  7. Connect the 2 electrical harness connectors to the EBCM (1).
  8. Secure the module (1) to the frame bracket (3) and fuel pipe shield (2) with the 2 nuts (4).
  9. Bleed the brake system. Refer to Antilock Brake System Automated Bleed Procedure .
  10. Return to Diagnostic Starting Point - Antilock Brake System .