GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2004 🢒 TopKick C-Series (Conventional) C4/C5 🢒 Engine 🢒 Engine Electrical 🢒 Engine Control Module Replacement

Removal Procedure

    Important: It is necessary to record the remaining engine oil life. If the replacement module is not programed with the remaining engine oil life, the engine oil life will default to 100%. If the replacement module is not programmed with the remaining engine oil life, the engine oil will need to be changed at 5000 km (3,000 mi) from the last engine oil change.

  1. Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life.
  2. Open the hood.
  3. Disconnect the battery.
  4. Remove accumulator bottle bracket retaining bolts and position bottle out of the way.
  5. Disconnect wiring harness connectors.

    6. Object Number: 808153 Size: SH
  6. Remove 2 multi-use bracket tray bolts and multi-use bracket tray.
  7. Remove 3 engine control module retainer nuts and the engine control module from the multi-use bracket tray.

Installation Procedure

    Notice: Refer to Fastener Notice in the Preface section.

  1. Install the engine control module retainer to the multi-use bracket tray with 3 bolts or nuts.

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


    Object Number: 808153 Size: SH
  2. Position the multi-use bracket tray in the multi-use bracket and secure with tray bolts.

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

  3. Connect the electrical wiring harness to the engine control module.
  4. Reposition the accumulator bottle in the accumulator bottle bracket.
  5. Install the accumulator bottle in the accumulator bottle bracket bolts.

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

  6. Connect the battery.
  7. Program the replacement ECM. Refer to Speed Calibration Programming in Programming.