Diagnostic Aids

WARNING: This page is about a different car, the 2009 Pontiac Torrent and 2009 Chevrolet Equinox. However, it is still accessible from the selected car via links, so may be relevant.

Check for the proper operation of the transmission shift selector.
Manually pushing in the ignition lock cylinder solenoid will allow the ignition key to be turned to OFF.
The ignition lock cylinder solenoid is part of the ignition lock cylinder case.
The park switch is part of the shift lock solenoid/switch assembly.