GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2002 🢒 Envoy - 2WD 🢒 Restraints 🢒 SIR 🢒 Inflatable Restraint Front End Discriminating Sensor Replacement

Removal Procedure
  1. Disable the SIR system. Refer to Disabling the SIR System .
  2. Remove the grille. Refer to Grille Replacement in Exterior Trim.

    3. Object Number: 842975 Size: SH
  3. Remove the headlamp wire harness from the retaining clip (1).

    4. Object Number: 842985 Size: SH
  4. Raise and support the headlamp wire harness (1) to gain access to the front end discriminating sensor.

    5. Object Number: 842968 Size: SH
  5. Loosen the bolts (1) retaining the discriminating sensor to the frame.

    6. Object Number: 742124 Size: SH
  6. Remove the discriminating sensor assembly from the frame (1).

    7. Object Number: 842979 Size: SH
  7. Position the discriminating sensor assembly above the front bumper.
  8. Remove the retaining bolts and protective cover (1) from the discriminating sensor.
  9. Remove the connector-position assurance (CPA) from the discriminating sensor electrical connector.
  10. Disconnect the discriminating sensor (2) electrical connector.
  11. Remove the discriminating sensor from the vehicle.

Installation Procedure

    Object Number: 842979 Size: SH
  1. Position the discriminating sensor assembly above the front bumper.
  2. Connect the discriminating sensor (2) electrical connector.
  3. Install the connector-position assurance (CPA) to the discriminating sensor electrical connector.
  4. Install the retaining bolts and protective cover (1) to the discriminating sensor.

    5. Object Number: 742124 Size: SH
  5. Position the discriminating sensor assembly to the frame (1).

    6. Object Number: 842968 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.

  6. Install the 2 bolts (1) retaining the discriminating sensor assembly to the frame.

    7. Tighten
    Tighten the front end discriminating sensor bolts to 8 N·m (71 lb in).


    Object Number: 842985 Size: SH
  7. Position the headlamp wire harness (1) to the retaining clip.

    8. Object Number: 842975 Size: SH
  8. Install and secure the headlamp wire harness in the retaining clip (1).
  9. Install the grille. Refer to Grille Replacement in Exterior Trim.
  10. Enable the SIR system. Refer to Enabling the SIR System .