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. Disconnect the negative battery cable.
  2. Remove the left rear fender brace. Refer to Front Fender Replacement in Body Front End.

  3. Object Number: 396416  Size: SH
  4. Remove the engine wiring harness junction block cover.

  5. Object Number: 368390  Size: SH
  6. Remove the positive battery cable bolt from the engine wiring harness junction block.

  7. Object Number: 396463  Size: SH
  8. Remove the chassis harness from the engine wiring harness junction block.

  9. Object Number: 396460  Size: SH
  10. Unsnap the engine wiring harness junction block from the bracket and pivot upward to access the connectors.
  11. Remove the forward lamp harness (32 way) connector from the engine wiring harness junction block.

  12. Object Number: 396470  Size: SH
  13. Remove the instrument panel harness (68 way) connector and the instrument panel harness (2 way) connector from the engine wiring harness junction block.

  14. Object Number: 396474  Size: SH
  15. Remove the engine harness (68 way) connector and the engine harness (1 way) connector from the engine wiring harness junction block.

  16. Object Number: 396477  Size: SH
  17. Remove the chassis harness (32 way) connector and the chassis harness (2 way) connector from the engine wiring harness junction block.

  18. Object Number: 396459  Size: SH
  19. Unsnap and remove the engine wiring harness junction block from the mounting bracket.

Installation Procedure


    Object Number: 396459  Size: SH
  1. Snap the engine wiring harness junction block into the mounting bracket.

  2. Object Number: 396477  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.

  3. Install the chassis harness (32 way) connector and the chassis harness (2 way) connector to the engine wiring harness junction block.
  4. Tighten
    Tighten the bolt to 6 N·m (53 lb in).


    Object Number: 396474  Size: SH
  5. Install the engine harness (68 way) connector and the engine harness (1 way) connector to the engine wiring harness junction block.
  6. Tighten
    Tighten the bolt to 6 N·m (53 lb in).


    Object Number: 396470  Size: SH
  7. Install the instrument panel harness (68 way) connector and the instrument panel harness (2 way) connector to the engine wiring harness junction block.
  8. Tighten
    Tighten the bolt to 6 N·m (53 lb in).


    Object Number: 396460  Size: SH
  9. Install the forward lamp harness (32 way) connector to the engine wiring harness junction block.
  10. Tighten
    Tighten the bolt to 6 N·m (53 lb in).

  11. Snap the engine wiring harness junction block to the bracket to close.

  12. Object Number: 396463  Size: SH
  13. Install the chassis harness to the engine wiring harness junction block.
  14. Tighten
    Tighten the bolt to 6 N·m (53 lb in).


    Object Number: 368390  Size: SH
  15. Install the positive battery cable bolt to the engine wiring harness junction block.
  16. Tighten
    Tighten the bolt to 9 N·m (80 lb in).


    Object Number: 396416  Size: SH
  17. Install the engine wiring harness junction block. cover.
  18. Install the left rear fender brace. Refer to Front Fender Replacement in Body Front End.
  19. Connect the negative battery cable.
  20. Tighten
    Tighten the bolt to 17 N·m (13 lb ft).