Circuit/System Testing

With the ignition ON, make sure no indicator(s) are illuminated in the instrument panel cluster (IPC) and perform the indicator diagnostic first if any indicator(s) are illuminated before performing the following diagnostics.
Turn the ignition OFF
Remove the key from the ignition.
Turn the headlamp switch OFF and open the driver door.
- If the chime does not sound, check for poor connections at the harness connector of the BCM.
With the ignition ON, install a scan tool and observe the Park Lamp Switch parameter in the BCM Exterior Lights Data List.
- The scan tool should display Inactive, but if the scan tool displays active refer to Park, License, and Tail Lamps Always On .
With the ignition ON, install a scan tool and observe the Headlamp Switch parameter in the BCM Exterior Lights Data List.
- The scan tool should display Inactive, but if the scan tool displays active refer to Headlamps Always On - Low or High Beam .
With the ignition turned OFF, disconnect the BCM connector C3.
With the ignition ON, install a scan tool and observe the Key-in-Ignition cylinder parameter in the BCM Inputs Data List.
- If the Key-in-Ignition cylinder parameter displays Active, replace the BCM.

If the Key-in-Ignition cylinder parameter displays Inactive, check the key-in-ignition switch signal circuit for a short to ground.

If the key-in-ignition switch circuit tests normal, replace the key-in-ignition switch.