2004 Pontiac Montana Owner's Manual - Page 212
2004 Pontiac Montana Manual
Page 212 highlights
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, from the front-seating area. 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. 3-30