2005 Pontiac Montana Owner's Manual - Page 193

Rear Climate Control System (Without Entertainment System) Your vehicle may have a rear climate control system that allows the driver to adjust the fan speed or a rear-seat passenger to set a separate temperature and adjust the fan speed, for the rear seating area. This system works with the main climate control system in your vehicle. This knob is located below the main climate control system on the instrument panel switchbank. Use this knob to adjust the fan speed for the rear seat passengers. These controls are overhead, on the control panel located behind the driver's seat. A rear seat passenger can use these controls to personally adjust the temperature and the fan speed for the rear seating area. The fan knob located on the switchbank must be turned to R (Rear) to allow the rear seat passengers to use the controls located on the control panel in the rear seating area. Performing this action disables the fan knob on the switchbank. To return control to that knob, turn the knob out of R. 3-29