1996 GMC Safari Owner's Manual - Page 128

Rear Heating System (Option) Rear Air Conditioning System (Option) You may have the optional rear heater. The three-speed fan switch is to the right of the radio. Turn the switch toward HIGH for higher airflow in the rear area. Turn the switch to the OFF position to turn the system off. You may have rear air conditioning. The rear air conditioning switch is located to the right of the heater controls. Turn the switch toward HIGH for higher airflow in the rear area. Turn the switch to the OFF position to turn the system off. 3-4