Action Taken When the DTC Sets

WARNING: This page is about a different car, the 2007 GMC Sierra and 2007 Chevrolet Silverado. However, it is still accessible from the selected car via links, so may be relevant.

The ECM will illuminate the malfunction indicator lamp (MIL) during the first trip in which the diagnostic test has been run and failed.
The ECM will signal the instrument panel cluster (IPC) to turn ON the Service Engine Soon indicator.
The ECM will alternately disable 2 groups of 4 cylinders by turning OFF the fuel injectors.
The ECM will store conditions which were present when the DTC set as Freeze Frame and File Records data.