Removal Procedure

Using a scan tool, retrieve the percentage of remaining engine oil. Record the remaining engine oil life.

Fig 1: View Of ECM/TCM & Cover
Courtesy of GENERAL MOTORS CORP.
Disconnect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection .
Disconnect the cooling fan electrical connector for additional clearance while removing the ECM.
Squeeze the ECM/transmission control module (TCM) cover upper retainers (1) in.
Remove the ECM/TCM cover.
Disconnect the engine wiring harness electrical connectors from the ECM.

Fig 2: View Of ECM
Courtesy of GENERAL MOTORS CORP.

NOTE: Refer to Handling Electrostatic Discharge Sensitive Parts Notice .
IMPORTANT:
- It is not necessary to disconnect the ECM electrical connectors in order to remove the ECM from the ECM/TCM bracket. Only disconnect the electrical connectors if servicing of component requires disconnecting of the electrical connectors.
- Remove any debris from around the ECM connector surfaces before servicing the ECM. Inspect the ECM module connector gaskets when diagnosing or replacing the ECM. Ensure that the gaskets are installed correctly. The gaskets prevent contaminant intrusion into the ECM.
Release the ECM/TCM bracket upper retainers (1).

Fig 3: Identifying ECM/TCM Bracket Upper Retainers
Courtesy of GENERAL MOTORS CORP.
Tilt the ECM away from the bracket and remove the ECM.
If replacement of the ECM/TCM bracket is required, remove the TCM. Refer to Transmission Control Module Replacement .

Fig 4: Identifying ECM/TCM Bracket & Retaining Bolts
Courtesy of GENERAL MOTORS CORP.
Remove the ECM/TCM bracket retaining bolts (2).
Remove the ECM/TCM bracket (1) from the vehicle frame.