2007 GMC Sierra 3500 HD Engine Control Module

You can install the bottom ECM tabs into the bracket, push the ECM in securing the ECM to the bracket, place the engine wiring harness lower electrical connector, place the engine wiring harness upper electrical connector, connect the negative battery cable and then program the ECM.

You should disconnect the electrical harness connector for the circuit being tested, enable the circuit and/or system being tested, connect the positive lead of the DMM to the point of the circuit to be tested and then connect the negative lead of the DMM to a good ground.

You should open the harness, remove all of the tapes, check and record the current flow direction and orientation of the diode, remove the inoperative diode, strip away a section of insulation next to the old soldered portion of the wire(s), check current flow direction of the new diode, attach the new diode to the wire(s), reinstall terminal(s) into the connector body and then tape the diode.

You should remove either the nut or bolt securing the main engine wiring harness ground terminal to the right cylinder head, remove all rust from the ground terminal, the cylinder head, and the retaining nut or bolt and place the main engine wiring harness ground terminal and install the nut or bolt.

You can retrieve the percentage of remaining engine oil, disconnect the negative battery cable, disengage the engine wiring harness upper electrical connector retainer, remove the connector, disengage, the engine wiring harness lower electrical connector retainer, disengage the retainer tabs securing the engine control module (ECM) to the bracket and then remove the ECM.