Circuit/System Description
WARNING: This page is about a different car, the 2007 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.
When the turn signal/multifunction switch is placed in the headlamps high or flash to pass (FTP) position, ground is applied to the body control module (BCM) through the headlamp high beam signal circuit or the flash to pass switch signal circuit. The BCM then applies ground to the headlamp high beam relay control circuit which energizes the high beam relay, applying battery voltage to the high beam headlamps. For more detailed information concerning headlamp operation refer to Exterior Lighting Systems Description and Operation .