Drive Mode Description And Operation (GMC): Notes

The drive mode system is a customer configurable control that allows the vehicle operator to tailor the vehicle operation and driveabiity parameters based on driving conditions. The drive mode is controlled by the vehicle operator through the S126 Drive Mode Select Switch. The S126 Drive Mode Select Switch is a momentary rotary knob with two internal switches and up to four LED indicators. Rotating the knob left or right will change to the next drive mode and the corresponding drive mode indicator on the switch will illuminate.

The S126 Drive Mode Select Switch is an input to the K20 Engine Control Module. When the knob is rotated, the K20 Engine Control Module will broadcast a message to all modules indicating the requested drive mode. Control modules that are involved in changing their operation based on differing drive modes will then change their operating values. The K9 Body Control Module will illuminate the appropriate drive mode indicator on the S126 Drive Mode Select Switch.

The components of the drive mode are:

• S126 Drive Mode Select Switch
• K20 Engine Control Module
• K9 Body Control Module

Other control modules or components that may respond to the commanded drive mode are:

• K17 Electronic Brake Control Module
• K43 Power Steering Control Module
• K47 Rear Differential Clutch Control Module
• K71 Transmission Control Module