Oldsmobile 1995 Silhouette Owner's Manual page 163

Rear Air Vents: To maximize airflow through the rear
heater outlet, place the left second row bucket seat in the
forward position (see "Adjusting Rear Seats" in the
Index).
The vent forward of the rear heater outlet is the cold air
return vent. Be sure to keep it free of obstructions.
Please keep the area around the base of the center
instrument panel console and between and under the
front seats free of objects that could obstruct airflow to
the rear.
I
OFF REAR LO MED HI
Rear Fan
--
Master Control: The master control for
the rear fan is located below the audio system.
To maintain a comfortable temperature in the rear area,
select the force of air you want, from LO to
HI,
by
sliding the control to the desired setting.
To transfer control of the rear fan to the rear control
switch, slide the master control to REAR. The rear
control switch will not operate when the master control
is in any other position.
To turn off the rear fan, slide the control to OFF.
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