Circuit/System Description
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 body control module (BCM) monitors the cruise control indicator dimming control switch and the cruise control switch signal circuits. When the cruise on/off switch is pressed ON, the steering wheel control switch assembly - left is closed and the signal circuits are high. When the cruise on/off switch is pressed OFF, the cruise control switch is open and the signal circuit are low.