1999 Pontiac Montana Owner's Manual - Page 206

yellowblue Rear Fan Control This option comes with the rear climate controls. Keep the area around the base of the center instrument panel console and the area between and under the front seats free of objects that would obstruct airflow to the rear of the vehicle. The rear fan control is located below the climate control system, in the switchbank. Rear Comfort Controls Turn the fan to the desired setting for the amount of air to be directed to the rear of the vehicle. The temperature of the air will be the same as the air in the front of the vehicle. The rear fan control in the instrument panel switchbank has an R setting which allows the rear passengers to use the rear climate control knobs to adjust the air through the rear air outlets. The rear climate control knobs are in a panel next to the second row seat. If your vehicle has the optional dual sliding doors, the panel is above the driver's seat. 3-6