Diagnostic Aids

WARNING: This page is about a different car, the 2008 Cadillac CTS. However, it is still accessible from the selected car via links, so may be relevant.

This test procedure requires that the vehicle battery has passed a load test and is completely charged. Refer to Battery Inspection/Test .
An open in the relay control circuit will cause no communication with the ECM when the ignition switch is cycled OFF and then ON after the initial failure. The malfunction indicator lamp (MIL) will flash rapidly and other relays can be heard turning on and off with the ignition ON.
When disconnecting electrical connectors or removing fuses and relays from a fuse block, always inspect the component electrical terminals for corrosion and the mating electrical terminals for tightness.
Use the J 35616 Connector Test Adapter Kit for any test that requires probing the underhood fuse block terminals, component wire harness terminals, or the ECM wire harness connector terminals.