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Driving with a Trailer
{CAUTION:
When towing a trailer, exhaust gases may collect
at the rear of the vehicle and enter if the liftgate,
trunk/hatch, or rear-most window is open.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
To maximize safety when towing a trailer:
Have the exhaust system inspected for leaks
and make necessary repairs before starting
a trip.
Never drive with the liftgate, trunk/hatch, or
rear-most window open.
Fully open the air outlets on or under the
instrument panel.
Adjust the Climate Control system to a setting
that brings in only outside air and set the fan
speed to the highest setting. See Climate
Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 2-30.Towing a trailer requires a certain amount of experience.
Get to know the rig before setting out for the open road.
Get acquainted with the feel of handling and braking with
the added weight of the trailer. And always keep in mind
that the vehicle you are driving is now longer and not as
responsive as the vehicle is by itself.
Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connectors, lamps,
tires and mirror adjustments. If the trailer has electric
brakes, start the vehicle and trailer moving and then
apply the trailer brake controller by hand to be sure the
brakes are working. This checks the electrical connection
at the same time.
During the trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer brakes
are still working.
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Driving On Grades
Reduce speed and shift to a lower gearbeforestarting
down a long or steep downgrade. If the transmission is
not shifted down, the brakes might have to be used so
much that they would get hot and no longer work well.
Vehicles can tow in D (Drive). Shift the transmission to
a lower gear if the transmission shifts too often under
heavy loads and/or hilly conditions.
When towing at high altitude on steep uphill grades,
consider the following: Engine coolant will boil at a lower
temperature than at normal altitudes. If the engine is
turned off immediately after towing at high altitude on
steep uphill grades, the vehicle may show signs similar to
engine overheating. To avoid this, let the engine run while
parked, preferably on level ground, with the automatic
transmission in P (Park) for a few minutes before turning
the engine off. For vehicles with manual transmissions,
let the engine run while parked, preferably on level
ground, with the transmission out of gear and the parking
brake applied, for a few minutes before turning the engine
off. If the overheat warning comes on, seeEngine
Overheating on page 5-34.
Parking on Hills
{CAUTION:
Parking the vehicle on a hill with the trailer
attached can be dangerous. If something goes
wrong, the rig could start to move. People can be
injured, and both the vehicle and the trailer can be
damaged. When possible, always park the rig on a
at surface.
If parking the rig on a hill:
1. Press the brake pedal, but do not shift into P (Park)
yet. Turn the wheels into the curb if facing downhill
or into traffic if facing uphill.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
brake pedal until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking
brake and shift into P (Park).
5. Release the brake pedal.
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The seven-wire harness contains the following trailer
circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Running Lamps
White: Ground
Light Green: Back-up Lamps
Dark Blue: Electric Brakes
Red: Battery Feed (The chassis wiring ring terminal
must be fastened to a stud on the underhood
electrical center before the trailer feed will become
active.)
If towing a light-duty trailer with a standard four-way
round pin connector, an adapter connector is available
from your dealer/retailer.
If charging a remote (non-vehicle) battery, turn on the
headlamps to boost the vehicle system voltage and
properly charge the battery.
The vehicle is also equipped with wiring for an electric
trailer brake controller. These wires are located inside the
vehicle on the driver’s side under the instrument panel.
These wires should be connected to an electric trailer
brake controller by your dealer/retailer or a quali ed
service center.The vehicle may be equipped with a four-pin trailer
towing harness. This harness has a four-pin trailer
connector that contains the following trailer circuits:
Yellow: Left Stop/Turn Signal
Dark Green: Right Stop/Turn Signal
Brown: Running Lamps
White: Ground
This harness also contains the following trailer circuits
that are not connected to the four-pin trailer connector:
Light Green: Back-Up Lamps
Dark Blue: Electric Brakes
Red: Battery Feed
If the vehicle is a 9–7X Aero, a trailer wiring harness
extension, and instructions for installing this extension,
were provided when the vehicle was delivered.
This extension will allow the vehicle’s trailer wiring
harness to be more easily accessible. There is a
four-way connector on the harness. A seven-way
adapter plug is also included if the trailer requires it.
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