Circuit/System Description
WARNING: This page is about a different car, the 2007 Chevrolet Malibu. However, it is still accessible from the selected car via links, so may be relevant.
The cruise control switch is an input to the body control module (BCM). The BCM monitors the cruise control on/off, set/coast, resume/accelerate, and cancel switch signal circuits in order to detect when a cruise control function switch has been activated. The BCM detects a predetermined voltage signal when a cruise control function switch is applied, with each switch having a different voltage value. The BCM sends a GMLAN serial data message to the ECM indicating the status of the cruise control switches.