You should turn the ignition, use a scan tool to retrieve the percentage of remaining engine oil and automatic transmission fluid life, measure the main relay circuit voltage at the ECM/TCM/IGN fuse in the underhood fuse block and at the TCM/BATT fuse in the underhood fuse block, disconnect the negative battery cable, remove the TCM/BATT fuse from the underhood fuse block and the ECM/TCM/IGN fuse from the underhood fuse block, unlock and disconnect the front engine wiring harness electrical connector from the ECM and the rear engine wiring harness electrical connector from the ECM, release the locking tabs, remove the ECM from the ECM bracket, depress the locking tabs on the ECM bracket and remove the ECM bracket.
By Bob
GM Specialist
01/11/2022
Q: What do we need to note when we service the Powertrain Control Module and Electrostatic Discharge?
A:
You should not touch the connector pins or soldered components on the circuit board to prevent possible electrostatic discharge (ESD) damage to the PCM.
By Bob
GM Specialist
01/11/2022
FAQ for Other Repair Info
Q: How to remove the Ignition Coil-Bank 2?
A:
You should turn the ignition off and remove the engine cover. If you are replacing the Ignition Coil for the cylinder, you should remove and reposition the intake manifold, disconnect the air cleaner duct from the throttle body and the positive crankcase ventilation (PCV) hose from the right bank camshaft cover and remove the intake manifold bolts, the intake manifold brace bolts and the brace and the upper intake manifold with the lower intake manifold to gain sufficient clearance for ignition coil removal. Then, you should remove the ignition coil electrical connector(s), the ignition coil bolt(s), and the ignition coil(s).
Q: How to install the Ignition Lock Cylinder Case?
A:
You should align the Ignition Lock Cylinder case assembly with the steering column tilt head assembly, secure the ignition lock cylinder case assembly to the steering column using 3 pan head tapping screws, install the ignition switch assembly, the ignition lock cylinder, the theft deterrent control module and the turn signal cancel cam and upper bearing and enable the SIR system.
Q: How to remove the Knock Sensor-Bank 1?
A:
You should turn the ignition off, raise and support the vehicle, reposition the wiring harness heat shield to obtain access, and remove the Knock Sensor (KS) electrical connector, the KS bolt, and the KS.