Alternative Fuels Engine Control Module Replacement for GMC Truck GMC C Sierra - 2WD (CNG) 2001
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.
- Disconnect
the negative battery cable. Refer to
Battery Negative Cable Disconnection and Connection
in Engine Electrical in the
C/K Pickup service manual.
- Raise and support the vehicle. Refer to
Lifting and Jacking the Vehicle
in General Information in the C/K
Pickup service manual.
- Remove the right side wheelhouse panel. Refer to
Wheelhouse Panel Replacement
in Body Front End in the C/K Pickup
service manual.
- Remove the ECM hold-down bracket (6) bolts (5)
from the ECM adapter bracket (4).
- Remove the ECM (7).
- Remove the connector position assurance locks and disconnect the
electrical connectors from the ECM (7).
If the ECM mounting and adapter brackets do not have to be removed proceed
to Step 3 of the Installation Procedure.
- Remove the ECM adapter bracket (4) bolts (8) from the ECM mounting
bracket (3).
- Remove the ECM adapter bracket (4) from the vehicle.
- Remove the ECM mounting bracket (3) bolts (2).
- Remove the ECM mounting bracket (3) from the vehicle.
Installation Procedure
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.
- Install the ECM
mounting bracket (3) loosely into the vehicle using the three mounting bolts
(2).
Tighten
Tighten the bolts to 9 N·m(7 lb ft).
- Install the ECM adapter bracket (4) to the ECM mounting bracket
(3) using the upper bolts (8).
Tighten
Tighten the bolts to 12 N·m(9 lb ft).
- Connect the electrical connectors to the ECM (7) and install the
connector position assurance locks.
- Place the top of the ECM into the upper portion of the ECM adapter
bracket (4).
- Ensure the ECM is properly positioned while installing the ECM
hold-down bracket (6) and bolts (5) into the ECM adapter bracket (4).
Tighten
Tighten the bolts to 12 N·m(9 lb ft).
- Install the right side wheelhouse panel. Refer to
Wheelhouse Panel Replacement
in Body Front End in the C/K Pickup
service manual.
- Lower the vehicle.
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.
- Install
the negative battery cable. Refer to
Battery Negative Cable Disconnection and Connection
in Engine Electrical in the
C/K Pickup service manual.
- Program the ECM with the correct Alternative Fuels software.