trailer GMC SIERRA 2010 User Guide

Tow/Haul Mode
Vehicles with an automatic transmission have a tow/
haul mode. The tow/haul mode adjusts the transmission
shift pattern to reduce shift cycling, providing increased
performance, vehicle control, and transmission cooling
when towing or hauling heavy loads.
The selector button is located on the end of the shift
lever. Turn the tow/haul on and off by pressing the
button. When the tow/haul is on, a light on the
instrument panel cluster will come on.
SeeTow/Haul Mode Light
on page 4‑49for more
information. Also see Tow Haul Mode under
Towing a Trailer
on
page 5‑50for more information.
Tow/Haul Mode (Allison Transmission®
or Hydra-Matic®6-Speed Automatic
Transmission)
Vehicles with an Allison or Hydra-Matic®6-speed
automatic transmission®have a tow/haul mode. The
tow/haul mode adjusts the transmission shift pattern to
reduce shift cycling, providing increased performance,
vehicle control, and transmission cooling when towing
or hauling heavy loads.
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Turn the tow/haul mode on and off by pressing the
button, located on the end of the shift lever. When the
tow/haul is on, a light on the instrument panel cluster
will come on.
SeeTow/Haul Mode Light
on page 4‑49for more
information.
Also see “Tow Haul Mode” underTowing a Trailer
on
page 5‑50for more information.
Grade Braking (Allison Transmission®
or Hydra-Matic®6-Speed Automatic
Transmission)
The Grade Braking shift modes can be activated by
pressing the button on the end of the shift control lever.
While in Range Selection Mode , Grade Braking is
deactivated allowing the driver to select a desired range
of gears.
Grade Braking is only active while the Tow/Haul Mode
is selected and you are not in the Range Selection
Mode. See “Tow/Haul Mode listed previously and
Automatic Transmission Operation
on page 3‑28for
more information on the Range Selection Mode. Grade
Braking assists in maintaining desired vehicle speeds
when driving on downhill grades by automatically
implementing a shift schedule that utilizes the engine
and transmission to slow the vehicle. This reduces wear
on the braking system and increases control of the vehicle. Grade Braking monitors vehicle speed,
acceleration, engine torque and brake pedal usage.
Using this information, it detects when the truck is on a
downhill grade and the driver desires to slow the vehicle
by pressing the brake.
Also see
Towing a Trailer
on page 5‑50for more
information.
Cruise Grade Braking (Allison
Transmission®or Hydra-Matic®
6-Speed Automatic Transmission)
Cruise Grade Braking assists when driving on a
downhill grade. It maintains vehicle speed by
automatically implementing a shift schedule that uses
the engine and the transmission to slow the vehicle.
Cruise Grade Braking operates while Cruise Control is
engaged in Tow/Haul mode to assist in maintaining
vehicle speed under loaded vehicle conditions.
It utilizes vehicle acceleration and deviation from
desired speed to determine the correct gear for the
operating condition. If vehicle speed is above the
desired speed the transmission will downshift to slow
the vehicle. If vehicle speed is near or below desired
speed the trans will upshift, allowing vehicle speed to
increase.
While in the Range Select Mode (RSM) mode, cruise
grade braking is not available.
See Automatic Transmission Operation on page 3‑28.
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Parking Brake
Set the parking brake by holding the regular brake
pedal down, then pushing down the parking brake
pedal.If the ignition is on, the brake system warning light will
come on. See
Brake System Warning Light
on
page 4‑39.
Notice: Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Make sure
that the parking brake is fully released and the
brake warning light is off before driving.
To release the parking brake, hold the regular brake
pedal down, then push down momentarily on the
parking brake pedal until you feel the pedal release.
Slowly pull your foot up off the park brake pedal. If the
parking brake is not released when you begin to drive,
the brake system warning light will flash and a chime
will sound warning you that the parking brake is still on.
If you are towing a trailer and are parking on a hill, see
Towing a Trailer on page 5‑50.
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Shifting Into Park
{WARNING:
It can be dangerous to get out of the vehicle if the
shift lever is not fully in P (Park) with the parking
brake firmly set. The vehicle can roll. If you have
left the engine running, the vehicle can move
suddenly. You or others could be injured. To be
sure the vehicle will not move, even when you are
on fairly level ground, use the steps that follow.
With four-wheel drive, if the transfer case is in
N (Neutral), the vehicle will be free to roll, even if
the shift lever is in P (Park). So, be sure the
transfer case is in a drive gear—not in
N (Neutral). If you are pulling a trailer, see Towing
a Trailer on page 5‑50.
1. Hold the brake pedal down, then set the parking brake.
See Parking Brake
on page 3‑50for more
information. 2. Move the shift lever into the P (Park) position by
pulling the shift lever toward you and moving it up
as far as it will go.
3. Be sure the transfer case is in a drive gear —not
in N (Neutral).
4. Turn the ignition key to LOCK/OFF.
5. Remove the key and take it with you. If you can leave the vehicle with the ignition key in your hand,
the vehicle is in P (Park).
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Running the Vehicle While Parked
It is better not to park with the engine running. But if you
ever have to, here are some things to know.
{WARNING:
Idling a vehicle in an enclosed area with poor
ventilation is dangerous. Engine exhaust may
enter the vehicle. Engine exhaust contains
Carbon Monoxide (CO) which cannot be seen or
smelled. It can cause unconsciousness and even
death. Never run the engine in an enclosed area
that has no fresh air ventilation. For more
information, seeEngine Exhaust on page 3‑54.
{WARNING:
It can be dangerous to get out of the vehicle if the
automatic transmission shift lever is not fully in
P (Park) with the parking brake firmly set. The
vehicle can roll. Do not leave the vehicle when the
engine is running unless you have to. If you have
(Continued)
WARNING: (Continued)
left the engine running, the vehicle can move
suddenly. You or others could be injured. To be
sure the vehicle will not move, even when you are
on fairly level ground, always set the parking
brake and move the shift lever to P (Park).
{WARNING:
Four-wheel drive vehicles with the transfer case in
N (Neutral) will allow the vehicle to roll, even if the
automatic transmission shift lever is in P (Park).
So, be sure the transfer case is in a drive
gear—not in N (Neutral). Always set the
parking brake.
Follow the proper steps to be sure the vehicle will not
move. See Shifting Into Park on page 3‑51.
If pulling a trailer, see Towing a Trailer on page 5‑50.
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Outside Towing Mirrors
If the vehicle has towing mirrors, they can be adjusted
for a clearer view of the objects behind you. Manually
pull out the mirror head to extend it for better visibility
when towing a trailer.
Manually fold the mirrors forward or rearward. The lower
portion of the mirror is convex. A convex mirror's
surface is curved to see more from the driver seat.
The convex mirror can be adjusted manually to the
driver preferred position for better vision.
The mirror may have a turn signal arrow that flashes in
the direction of the turn or lane change.
Outside Power Mirrors
Vehicles with outside
power mirrors have
controls located on the
driver door.
To adjust each mirror: 1. Press (A) or (B) to select the driver or passenger side mirror.
2. Press one of the four arrows located on the control pad to adjust the mirror.
3. Adjust the outside mirror so that the side of the vehicle and the area behind are seen.
4. Press either (A) or (B) again to deselect the mirror.
Manually fold the mirrors inward to prevent damage
when going through an automatic car wash. To fold,
push the mirror toward the vehicle. Push the mirror
outward, to return to its original position.
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When the System Does Not Seem to
Work Properly
If the URPA system will not activate due to a temporary
condition, the messages PARK ASSIST OFF or PARK
ASST BLOCKED SEE OWNERS MANUAL will be
displayed on the DIC.
SERVICE PARK ASSIST :If this message occurs, take
the vehicle to your dealer/retailer to repair the system.
PARK ASSIST OFF : This message occurs if the driver
disables the system.
PARK ASST BLOCKED SEE OWNERS MANUAL :
This message can occur under the following conditions:
.The ultrasonic sensors are not clean. Keep the
vehicle's rear bumper free of mud, dirt, snow, ice
and slush. For cleaning instructions, see Washing
Your Vehicle on page 6‑113.
.The park assist sensors are covered by frost or
ice. Frost or ice can form around and behind the
sensors and may not always be seen; this can
occur after washing the vehicle in cold weather.
The message may not clear until the frost or ice
has melted.
.A trailer was attached to the vehicle, or a bicycle or
an object was hanging out of the tailgate during the
last drive cycle. Once the attached object is
removed and the tailgate is raised, URPA will
return to normal operation.
.A tow bar is attached to the vehicle.
.The vehicle's bumper is damaged. Take the vehicle
to your dealer/retailer to repair the system.
.Other conditions may affect system performance,
such as vibrations from a jackhammer or the
compression of air brakes on a very large truck.
If the system is still disabled, after driving forward at
least 40 km/h (25 mph), take the vehicle to your
dealer/retailer.
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Electric Power Management
The vehicle has Electric Power Management (EPM) that
estimates the battery's temperature and state of charge.
It then adjusts the voltage for best performance and
extended life of the battery.
When the battery's state of charge is low, the voltage is
raised slightly to quickly bring the charge back up.
When the state of charge is high, the voltage is lowered
slightly to prevent overcharging. If the vehicle has a
voltmeter gage or a voltage display on the Driver
Information Center (DIC), you may see the voltage
move up or down. This is normal. If there is a problem,
an alert will be displayed.
The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles. This is
because the generator (alternator) may not be spinning
fast enough at idle to produce all the power that is
needed for very high electrical loads.
A high electrical load occurs when several of the
following are on, such as: headlamps, high beams, fog
lamps, rear window defogger, climate control fan at high
speed, heated seats, engine cooling fans, trailer loads,
and loads plugged into accessory power outlets.EPM works to prevent excessive discharge of the
battery. It does this by balancing the generator's output
and the vehicle's electrical needs. It can increase
engine idle speed to generate more power, whenever
needed. It can temporarily reduce the power demands
of some accessories.
Normally, these actions occur in steps or levels,
without being noticeable. In rare cases at the highest
levels of corrective action, this action may be noticeable
to the driver. If so, a Driver Information Center (DIC)
message might be displayed, such as BATTERY
SAVER ACTIVE, BATTERY VOLTAGE LOW, or
LOW BATTERY. If this message is displayed, it is
recommended that the driver reduce the electrical loads
as much as possible. See
DIC Warnings and Messages
on page 4‑65.
Battery Run-Down Protection
This feature shuts off the dome and reading lamps,
if they are left on for more than 10 minutes after the
ignition is turned off. The cargo lamp shuts off after
20 minutes. This prevents the battery from
running down.
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This light comes on during a malfunction in one of
two ways:
Light Flashing :A misfire condition has been detected.
A misfire increases vehicle emissions and could
damage the emission control system on the vehicle.
Diagnosis and service might be required.
To prevent more serious damage to the vehicle:
.Reduce vehicle speed.
.Avoid hard accelerations.
.Avoid steep uphill grades.
.If towing a trailer, reduce the amount of cargo
being hauled as soon as it is possible.
If the light continues to flash, when it is safe to do so,
stop the vehicle. Find a safe place to park the vehicle.
Turn the key off, wait at least 10 seconds, and restart
the engine. If the light is still flashing, follow the
previous steps and see your dealer/retailer for service
as soon as possible. Light On Steady :
An emission control system
malfunction has been detected on the vehicle.
Diagnosis and service might be required.
An emission system malfunction might be corrected by
doing the following:
.Make sure the fuel cap is fully installed. See Filling
the Tankon page 6‑11. The diagnostic system
can determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap
allows fuel to evaporate into the atmosphere.
A few driving trips with the cap properly installed
should turn the light off.
.If the vehicle has been driven through a deep
puddle of water, the vehicle's electrical system
might be wet. The condition is usually corrected
when the electrical system dries out. A few driving
trips should turn the light off.
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DIC Buttons
The buttons are the
trip/fuel, vehicle
information,
customization, and
set/reset buttons.
The button functions
are detailed in the
following pages.
3(Trip/Fuel):Press this button to display the
odometer, trip odometer, fuel range, average economy,
fuel used, timer, instantaneous economy and Active
Fuel Management™ indicator, and transmission
temperature. The compass and outside temperature will
also be shown in the display. The temperature will be
shown in °F or °C depending on the units selected.
T(Vehicle Information): Press this button to display
the oil life, units, tire pressure readings for vehicles with
the Tire Pressure Monitor System (TPMS), trailer brake
gain and output information for vehicles with the Integrated Trailer Brake Control (ITBC) system, engine
hours, Remote Keyless Entry (RKE) transmitter
programming, compass zone setting, and compass
recalibration.
U(Customization):
Press this button to customize the
feature settings on your vehicle. See DIC Vehicle
Customization (With DIC Buttons)
on page 4‑75for
more information.
V(Set/Reset): Press this button to set or reset certain
functions and to turn off or acknowledge messages on
the DIC.
Trip/Fuel Menu Items
3
(Trip/Fuel): Press this button to scroll through the
following menu items:
Odometer
Press the trip/fuel button until ODOMETER displays.
This display shows the distance the vehicle has been
driven in either miles (mi) or kilometers (km). Pressing
the trip odometer reset stem will also display the
odometer.
To switch between English and metric measurements,
see “Units” later in this section.
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