GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Astro - 2WD 🢒 Engine 🢒 Engine Electrical 🢒 Brake Pressure Modulator Valve Replacement

Removal Procedure

    Caution: Refer to Battery Disconnect Caution in the Preface section.

  1. Disconnect the negative battery cable.
  2. Raise the vehicle.

    3. Object Number: 394904 Size: SH
  3. Remove two 13 mm weld/stud nuts fastening the shield and the BPMV to the EHCU mounting bracket.
  4. Disconnect the four electrical connectors from the EBCM.
  5. Remove the electrical connector (9) from the combination valve (11).
  6. Remove the front and rear brake pipes from the combination valve (11).
  7. Remove three hydraulic lines from the tube adapters (5) on the BPMV (3).
  8. Remove the EHCU from the vehicle.
  9. Remove the four T-25 TORX® screws (1) that fasten the EBCM (2) to the BPMV (3).

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

  10. Remove the EBCM (2) from the BPMV (3).
  11. Remove three Allen bolts (10) from the combination valve (11).
  12. Remove the combination valve (11) from the BPMV (3).

    13. Important: Do not reuse the transfer tubes. Always install new transfer tubes.

  13. Remove two transfer tubes (12).
  14. Remove three 13 mm bolts (8) retaining the BPMV (3) to the base bracket (6).

Installation Procedure

    Object Number: 394904 Size: SH
  1. Install new transfer tubes (13) into the combination valve (12) until fully seated.
  2. Install the combination valve (12) to the BPMV (4).
  3. Install three allen bolts (11) that fasten the combination valve to the BPMV.

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

  4. Install the EBCM (2) to the BPMV (3).

    5. 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.

  5. Install four new T-25 TORX® screws (1) in the EBCM (2).

    6. Tighten
    Tighten the four T-25 TORX® screws to 5 N·m (39 lb in) in an X-pattern.

  6. Install three 13 mm EHCU to bracket retaining bolts (8).

    7. Tighten
    Tighten three 13 mm bolts to 9 N·m (7 lb ft).

  7. Install the EHCU to the vehicle.
  8. Install the front and rear brake pipes to the combination valve (11).

    9. Tighten
    Tighten the brake pipe fitting to 24 N·m (18 lb ft).

  9. Install three hydraulic lines to the tube adapters (5) on the BPMV (3).

    10. Tighten
    Tighten the three hydraulic lines to 30 N·m (22 lb ft).

  10. Connect the 2 way electrical connector (9) the combination valve (11).
  11. Connect four electrical connectors to the EBCM (2).
  12. Install two 13 mm weld/stud nuts fastening the shield and the BPMV to the EHCU mounting bracket.

    13. Tighten
    Tighten two 13 mm weld/stud nuts to 24 N·m (18 lb ft).

  13. Lower the vehicle.
  14. Connect the negative battery cable.
  15. Bleed the system. Refer to Antilock Brake System Automated Bleed Procedure .

    16. Important: Verify that the combination valve metering rod is not depressed during bleeding.

  16. Revise the tire calibration using the Scan Tool .
  17. Go to Diagnostic System Check - ABS .