GMC 1995 Safari Owner's Manual page 120

Engine Coolant Heater (Option)
If you use the optional engine coolant heater before starting your engine,
your heating system will produce warmer air faster to heat the passenger
compartment in cold weather. See "Engine Coolant Heater" in the Index.
Rear Heater (Option)
Rear Air Conditioning (Option)
You may have the
optional rear heater.
The three speed fan
switch is above the
radio. Slide the lever
toward HI for warmer
air in the rear area.
Move the switch to
OFF to turn the
system off.
You may nave rear air
conditioning. The rear
air conditioning
switch is located
above the radio at the
top of the instrument
panel. Slide the lever
toward
HI
for cooler
air in the rear area.
Slide the lever to OFF
to
turn the system off.
If your vehicle has rear air conditioning, setting it on LO may enhance front
A/C performance by allowing trapped refrigerant in rear lines to circulate.
The system will only send cooled air if the front system is on. It can still be
used to circulate air, even if the front system is off.
Before using the rear air conditioning, open the windows to clear the vehicle
of hot air. Close the windows when using the system.
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