GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

  1. Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .

  2. Object Number: 1343784  Size: SH
  3. Remove the fasteners retaining the positive battery cable leads to the underhood junction block, then reposition the cable lead away from the junction block.

  4. Object Number: 1343776  Size: SH
  5. Remove the relay cover.
  6. Remove all of the fuses and the relays.

  7. Object Number: 1343780  Size: SH
  8. Use a hook-type tool to disengage the 4 tabs that secure the junction block to the battery tray.

  9. Object Number: 1343783  Size: SH
  10. Use a flat-bladed tool to remove the connector cover from the junction block.

  11. Object Number: 1343778  Size: SH
  12. Loosen the 4 bolts across the top of the junction block.

  13. Object Number: 1343779  Size: SH
  14. Use a flat-bladed tool to remove the locking pins from the body harness connector.
  15. Disconnect the body harness connector.
  16. Disconnect the remaining wiring harness connectors from the junction block.

Installation Procedure


    Object Number: 1343776  Size: SH
  1. With the junction block turned upside down, install the junction block harness connectors into the junction block.

  2. Object Number: 1343779  Size: SH
  3. Install the locking pin to the power supply connector.
  4. Notice: Refer to Fastener Notice in the Preface section.

  5. Install the bolts retaining the engine, instrument panel (I/P), and forward lamp wiring harness connectors to the junction block.
  6. Tighten
    Tighten the electrical center junction block bolts to 7 N·m (62 lb in).


    Object Number: 1343778  Size: SH
  7. Install the junction block connector cover.
  8. Turn the junction block right side up.
  9. Install the junction block to the battery tray by pushing the electrical center into the retainer tab.
  10. Install all of the fuses and the relays.
  11. Install the positive battery cable lead to the stud on underhood junction block, then install the positive battery cable lead retaining nut.
  12. Tighten
    Tighten the positive battery cable lead retaining nut to 10 N·m (89 lb in).

  13. Install the relay cover.
  14. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .