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.
Turn the mode knob on the far right clockwise or
counterclockwise to direct the airflow inside of your
vehicle.
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.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 the vehicle to cool down. It also helps the
system to operate more efficiently.
<(Maximum Air Conditioning):Turn the right knob
to this setting for maximum cooling. This setting
puts the system in recirculation mode and helps to
maximize your air conditioner’s performance and your
vehicle’s fuel economy. This setting also cools the
air the fastest.
Y(Air Conditioning):This setting is used for normal
cooling on hot days. It cools outside air and directs
it through the instrument panel vents.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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