GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2005 🢒 GMC C Sierra - 2WD 🢒 Engine 🢒 Engine Electrical 🢒 Generator Control Module Replacement

Removal Procedure

    Object Number: 1237061 Size: SH
  1. Disconnect the generator battery carrier. Refer to Hybrid Battery Service Disconnect/Connect .
  2. Remove the air cleaner assembly. Refer to Air Cleaner Assembly Replacement for the 4.8L, 5.3L, and 6.0L engines.
  3. Remove the surge tank. Refer to Radiator Surge Tank Replacement .
  4. Remove the generator control module (GCM) coolant tank. Refer to Generator Control Module Coolant Tank Replacement .
  5. Remove the GCM cover bolts, and cover.
  6. Remove the 3-phase cable nuts to the GCM.
  7. Remove the 3-phase cable from the GCM.

    8. Object Number: 1480429 Size: SH
  8. Remove the connector position assurance (CPA) retainer on the engine harness electrical connector.
  9. Disconnect the engine harness electrical connector.

    10. Object Number: 1257479 Size: SH
  10. Disconnect the accessory power receptacle electrical connector from the GCM.

    11. Object Number: 1480439 Size: SH
  11. Reposition the GCM coolant outlet hose clamp (2).
  12. Remove the GCM coolant outlet hose (1).

    13. Object Number: 1237045 Size: SH
  13. Loosen the 14-volt positive/negative battery cable bolt (1).
  14. Remove the red CPA retainer.
  15. Disconnect the 14-volt positive/negative battery cable.

    16. Object Number: 1237049 Size: SH
  16. Loosen the 42-volt positive/negative battery cable bolt (1).
  17. Remove the red CPA retainer.
  18. Disconnect the 42-volt positive/negative battery cable.
  19. Disconnect the 42-volt jumper ground wire connector (2).

    20. Object Number: 1237056 Size: SH
  20. Remove the GCM rear bolt (2).
  21. Remove the GCM front bolt (3).
  22. Remove the brace (4).
  23. Remove the GCM.

Installation Procedure

    Object Number: 1237056 Size: SH
  1. Install the GCM.
  2. Install the brace (4).
  3. Install the GCM front bolt (3).

    4. Notice: Refer to Fastener Notice in the Preface section.

  4. Install the GCM rear bolt (2).

    5. Tighten
    Tighten the bolts to 20 N·m (15 lb ft).


    Object Number: 1237049 Size: SH
  5. Connect the 42-volt jumper ground wire connector (2).
  6. Connect the 42-volt positive/negative battery cable.
  7. Install the red CPA retainer.
  8. Tighten the 42-volt positive/negative battery cable bolt (1).

    9. Tighten
    Tighten the bolt to 9 N·m (80 lb in).


    Object Number: 1237045 Size: SH
  9. Connect the 14-volt positive/negative battery cable.
  10. Install the red CPA retainer.
  11. Tighten the 14-volt positive/negative battery cable bolt (1).

    12. Tighten
    Tighten the bolt to 9 N·m (80 lb in).


    Object Number: 1480439 Size: SH
  12. Install the GCM coolant outlet hose (1).
  13. Position the GCM coolant outlet hose clamp (2).

    14. Object Number: 1257479 Size: SH
  14. Connect the accessory power receptacle electrical connector to the GCM.

    15. Object Number: 1480429 Size: SH
  15. Connect the engine harness electrical connector.
  16. Install the CPA retainer on the engine harness electrical connector.

    17. Object Number: 1237061 Size: SH
  17. Install the 3-phase cable to the GCM.
  18. Install the 3-phase cable nuts to the GCM.

    19. Tighten
    Tighten the nuts to 15 N·m (11 lb ft).

  19. Install the GCM cover and bolts.

    20. Tighten
    Tighten the bolts to 9 N·m (80 lb in).

  20. Install the GCM coolant tank. Refer to Generator Control Module Coolant Tank Replacement .
  21. Install the surge tank. Refer to Radiator Surge Tank Replacement .
  22. Install the air cleaner assembly. Refer to Air Cleaner Assembly Replacement for the 4.8L, 5.3L, and 6.0L engines.
  23. Connect the generator battery carrier. Refer to Hybrid Battery Service Disconnect/Connect .
  24. Program the GCM. Refer to Control Module References for programming and setup information.