To change the current mode, select one of the
following:
9(Off):This setting turns the system off.
H(Vent):This mode directs air to the instrument
panel vents.
)(Bi-Level):This mode directs half of the air to
the instrument panel vents, then directs the
remaining air to the floor vents. Cooler air is
directed to the upper vents and warmer air to the
floor vents.
6(Floor):This mode directs most of the air to
the floor vents. Use this mode to send air to
the rear of the vehicle. Keep the area under the
front seats free of objects that could obstruct
airflow to the rear of the vehicle.
The mode knob can also be used to select the
defrost mode. For more information, see
“Defogging and Defrosting” later in this section.
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan
speed. To increase airflow, turn the knob clockwise.
To decrease airflow, turn it counterclockwise. To
turn the fan off, turn the mode knob on the far right
counterclockwise to the off position.Temperature Knob:Turn the middle knob
located clockwise or counterclockwise to increase
or decrease the temperature inside of your
vehicle. Turn the knob toward the red area for
warmer air. Turn the knob toward the blue area for
cooler air.
If your vehicle has air conditioning, the controls
will look like this:
On hot days, open the windows to let hot inside
air escape; then close them. This helps to reduce
the time it takes for your vehicle to cool down.
It also helps the system to operate more efficiently.
Vehicles With Air Conditioning
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Trailer Connections
Heavy-Duty Trailer Wiring Package
Your vehicle may be equipped with an eight-wire
trailer towing harness. This harness, with a
seven-pin universal heavy-duty trailer connector,
is attached to a bracket on the platform hitch.
The Center High-Mounted Stoplamp (CHMSL)
wire is tied next to the trailer wiring harness for
use with a trailer.
The eight-wire harness contains the following
trailer circuits:
•Yellow: Left Stop/Turn Signal
•Dark Green: Right Stop/Turn Signal
•Brown: Taillamps
•White: Ground
•Light Green: Back-up Lamps
•Light Blue: CHMSL
•Red: Battery Feed
•Dark Blue: Trailer Brake
Trailer Connections
(C7/C8 Models Only)
If your vehicle has these trailer connections, they
are located at the rear of the cab for a tractor
and at the rear of the chassis when towing
a trailer. There will be an air connection and an
electrical connection.
Be sure that the couplings to the trailer are
made correctly.
Air Connections
If you are not connecting the trailer air line
connections to another piece of equipment,
be sure to replace their protective caps.
Electrical Connections
This system is a seven-wire cable that will
connect to the trailer, supplying power to the
trailer’s lighting system. When not in use, it
is stored in the trailer air-hose storage bracket.
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