Cruise Control Switch: Notes

WARNING: This page is about a different car, the 2009 Cadillac STS. However, it is still accessible from the selected car via links, so may be relevant.

The cruise control switch, functionally is a common feature that is shared between the Adaptive Cruise Control (ACC) System and the regular Cruise Control System. The ACC System will not operate if any cruise switch fails. The cruise control switch comprises the following cruise control function switches:

On/off switch
Set/decrease switch
Resume/increase switch

The cruise control function switches are arranged in a resistive ladder design whereby each switch function is set up with different resistance values. The instrument panel module (IPM) through the cruise control switch signal circuit detects a predetermined voltage value when any cruise control switch function is activated. The associated cruise control function signal detected by the IPM is then sent to the engine control module (ECM) as a GMLAN serial data circuit message. The ECM on receiving the message provides the cruise control function requested by the IPM. The ECM is responsible for recognizing and responding to cruise control switch requests sent by the IPM. The cruise control function switches are used by the ECM to communicate to the distance sensing cruise control (DSCC) module the driver selected vehicle speed. The driver selected vehicle speed is communicated through GMLAN serial data circuit to the DSCC module and the IPM. The ACC System engages and adjusts vehicle speeds based on the activation of the following cruise control function switches: