GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2000 🢒 Firefly (Canada) 🢒 Brakes 🢒 Antilock Brake System 🢒 Brake Modulator Replacement

Removal Procedure

    Object Number: 240672 Size: SH
  1. Remove the brake modulator assembly. Refer to Brake Pressure Modulator Valve Assembly Replacement .
  2. Remove the 4 screws (1) that retain both ABS brake solenoids from the hydraulic modulator assembly (4).
  3. Remove both brake solenoids (2) from the hydraulic modulator assembly (4).

    4. Object Number: 221843 Size: MH
  4. Remove the screws (5) attaching the gear cover (4).
  5. Remove the gear cover (4).
  6. Remove the 4 screws (6) attaching the motor pack (1) to the hydraulic brake modulator (2).

    7. Important: Use care when handling the motor pack to ensure the motor pack connector is not damaged, or accidental intrusion of brake fluid into the motor pack does not occur. This may result in a premature failure of the motor pack.

    Important: Take care in handling the motor pack. If dropped or damaged during handling, the motor pack must be replaced.

  7. Remove the motor pack (1) from the hydraulic brake modulator (2).

Installation Procedure

    Object Number: 165951 Size: SH
  1. With the ABS brake modulator positioned upside down, and the gears facing you, rotate each ABS brake modulator gear clockwise until movement stops.

    2. The procedure causes the following conditions:

    • The pistons are positioned very close to the top of the modulator bore.
    • The brake bleeding procedure is simplified.

    Object Number: 221843 Size: MH
  2. Install the ABS brake motor pack (1) onto the hydraulic brake modulator (2). Aligning the three motor pack gears with the modulator gears.

    3. 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.

  3. Install the 4 screws (6) that retain the motor pack (1) to the hydraulic brake modulator (2).

    4. Tighten
    Tighten the 4 screws to 5 N·m (44 lb in).

  4. Install the gear cover (4) to the hydraulic brake modulator/motor pack assembly (2).
  5. Install the screws (5) that retain the gear cover (4).

    6. Tighten
    Tighten the screws to 4 N·m (36 lb in).


    Object Number: 240672 Size: SH
  6. Install the ABS brake solenoids (2) to the hydraulic brake modulator/motor pack assembly.
    7. • Lubricate the solenoid seals (3) with clean brake fluid.
    • Verify that the solenoid seal (3) is properly positioned to each solenoid.
    • Position solenoids so that their electrical connectors will face the same direction prior to removal.
    • By hand, press down firmly on the solenoids until their flanges seat onto the hydraulic modulator.
  7. Install the four Torx® head bolts (1) that retain the brake solenoids.

    8. Tighten
    Tighten the Torx® head screws to 5 N·m (44 lb in).

  8. Install the brake modulator assembly. Refer to Brake Pressure Modulator Valve Assembly Replacement .
  9. Perform the Diagnostic System Check - ABS .