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If the vehicle’s brake, anti-lock brake or StabiliTrak
systems are not functioning properly, the ITBC system
may not be fully functional or may not function at all.
Make sure all of these systems are fully operational to
ensure full functionality of the ITBC system.
The ITBC system is powered through the vehicle’s
electrical system. Turning the ignition off will also turn off
the ITBC system. The ITBC system is fully functional only
when the ignition is in ON or in RUN.
The ITBC system can only be used with trailers with
electric brakes.
{CAUTION:
Connecting a trailer that is not compatible with the
ITBC system may result in reduced or complete
loss of trailer braking. There may be an increase in
stopping distance or trailer instability which could
result in personal injury or damage to the vehicle,
trailer, or other property. An aftermarket controller
may be available for use with trailers with surge, air
or electric-over-hydraulic trailer brake systems.
To determine the type of brakes on the trailer and
the availability of controllers, check with your trailer
manufacturer or dealer/retailer.When trailering, make sure of the following:
The ITBC system is used only with trailers that are
equipped with electric brakes.
All applicable local and federal laws and regulations
are followed.
All electrical and mechanical connections to the
trailer are made correctly.
The trailer’s brakes are in proper working condition.
The trailer and vehicle are properly loaded for
the towing condition.
The ITBC system is a factory installed item.
Out-of-factory installation of this system should not be
attempted. GM is not responsible for warranty or
performance of the system resulting from out-of-factory
installation.
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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 2-55.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.
While towing a trailer or when exposed to long periods
of sunshine, the oor of the truck bed may become
very warm. Avoid putting items in the truck bed
that might be affected by high ambient temperatures.
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Maintenance When Trailer Towing
The vehicle needs service more often when pulling a
trailer. See this manual’s Maintenance Schedule
or Index for more information. Things that are especially
important in trailer operation are automatic transmission
uid, engine oil, axle lubricant, belts, cooling system
and brake system. It is a good idea to inspect
these before and during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
The vehicle is equipped with one of the following wiring
harnesses for towing a trailer or hauling a slide-in
camper.
Basic Trailer Wiring
All regular, extended cab and crew cab pickups have a
seven-wire trailer towing harness.
For vehicles not equipped with heavy duty trailering, the
harness is secured to the vehicle’s frame behind the
spare tire mount. The harness requires the installation of
a trailer connector, which is available through your
dealer/retailer.
If towing a light-duty trailer with a standard four-way
round pin connector, an adapter is available from your
dealer/retailer.
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