2007 GMC SIERRA cooling

Remote Vehicle Start
Your vehicle may have a remote starting feature.
This feature allows you to start the engine
from outside of the vehicle. It may also start up
the vehicle’s heating or air conditioning systems
and rear window defogger. Normal operation of the
system will return after the key is turned to the
RUN position.
During a remote start, if your vehicle has an
automatic climate control system, the climate
control system will default to a heating mode
during colder outside temperatures and a cooling
mode during warmer outside temperatures. If
your vehicle does not have an automatic climate
control system, during remote start, the climate
control system will turn on at the setting the vehicle
was set to when the vehicle was last turned off.
During a remote start, if your vehicle has an
automatic climate control system and heated
seats, the heated seats will turn on during colder
outside temperatures and will shut off when
the key is turned to RUN.If your vehicle does not have an automatic climate
control system, during remote start, you will
need to manually turn the heated seats on and off.
SeeHeated Seats on page 12for additional
information.
Laws in some communities may restrict the use of
remote starters. For example, some laws may
require a person using the remote start to have the
vehicle in view when doing so. Check local
regulations for any requirements on remote starting
of vehicles.
Do not use the remote start feature if your vehicle
is low on fuel. Your vehicle may run out of fuel.
The RKE transmitter with the remote start button,
provides an increased range of operation.
However, the range may be less while the vehicle
is running. As a result, you may need to be
closer to your vehicle to turn it off, than you were
to turn it on.
There are other conditions which can affect the
performance of the transmitter, seeRemote
Keyless Entry (RKE) System on page 110for
additional information.
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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 266for more
information.
Also see Tow Haul Mode underTowing a Trailer
on page 445for more information.Tow/Haul Mode (Allison Transmission®
or Hydra-Matic®6-Speed Automatic
Transmission)
If your vehicle has an Allison or Hydra-Matic®
6-speed automatic transmission®, it has 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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Your vehicle may also have reading lamps in
other locations. To turn the lamps on or off, press
the button located next to the lamp.
If your vehicle has a DVD Rear Seat Entertainment
(RSE) system, press the lamp lenses to turn the
lamps on or off.
The lamps are xed and cannot be adjusted.
Cargo Lamp
The cargo lamps come on by turning the
instrument panel brightness control knob to the
farthest clockwise position. This knob is located on
the instrument panel and also turns on the
dome lamps.
The cargo lamp can be used if more light is
needed in the cargo area of the vehicle or in the
top-box storage units.
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 put the charge
back in. When the state of charge is high, the
voltage is lowered slightly to prevent overcharging.
If the vehicle has a voltmeter gage or 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 loads are on: 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.
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Climate Controls
Climate Control System (With Air
Conditioning)
With this system you can control the heating,
cooling, and ventilation for your vehicle.
Operation
9
(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan
speed. Turn the knob all the way counterclockwise
to turn the front system off.Temperature Control:Turn the center knob
clockwise or counterclockwise to increase
or decrease the temperature inside the vehicle.
Use the right knob to select from the
following modes:
The right knob can be positioned between
two modes to select a combination of those
two modes.
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs half of the air to
the instrument panel outlets and half to the
oor outlets.
6(Floor):This mode directs most of the air to
the oor outlets with some air directed to the
windshield and side window outlets. In this mode,
the system will automatically select outside air.
Recirculation cannot be selected in oor mode.
The right knob may also be used to select the
defrost and defog mode. For more information, see
“Defogging and Defrosting” later in this section.
234

Climate Control System
(Heater Only)
With this system you can control the heating,
cooling, and ventilation for your vehicle.
Operation
9
(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan
speed. Turn the knob all the way counterclockwise
to turn the front system off.Temperature Control:Turn the center knob
clockwise or counterclockwise to increase
or decrease the temperature inside the vehicle.
Use the right knob to select from the
following modes:
The right knob can be positioned between
two modes to select a combination of those
two modes.
H(Vent):This mode directs air to the instrument
panel outlets.
)(Bi-Level):This mode directs half of the air to
the instrument panel outlets and to the oor outlets.
6(Floor):This mode directs most of the air to
the oor outlets with some air directed to the
windshield, side window outlets, and second row
oor outlets. In this mode, the system will
automatically select outside air.
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Defogging and Defrosting
Fog or frost on the inside of windows is a result of
high humidity (moisture) condensing on the cool
window glass. This can be minimized if the climate
control system is used properly.
Turn the right knob to select the defog or
defrost mode.
-(Defog):This mode clears the windows of fog
or moisture and warm the passengers. The air
is directed to the windshield, oor outlets, and side
window vents.
0(Defrost):This mode removes fog or frost
from the windshield more quickly. A portion of the
air is directed to the windshield and the side
window vents, with some air directed to the oor
vents. The system will automatically force
outside air into the vehicle.
Do not drive the vehicle until all the windows
are clear.
Dual Automatic Climate
Control System
With this system, you can control the heating,
cooling, and ventilation in the vehicle. The vehicle
also has a ow-through ventilation system
described later in this section.
You can select different climate control settings for
the driver and passengers.
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2. Set the driver’s and passenger’s temperature.
To nd your comfort setting, start with a 74°F
(23°C) temperature setting and allow about
20 minutes for the system to regulate. Use the
driver’s or passenger’s temperature buttons to
adjust the temperature setting as necessary.
If you choose the temperature setting of 60°F
(15°C), the system will remain at the maximum
cooling setting. If you choose the temperature
setting of 90°F (32°C), the system will remain
at the maximum heat setting. Choosing either
maximum setting will not cause the vehicle to
heat or cool any faster.
Be careful not to cover the solar sensor located on
the top of the instrument panel near the
windshield. This sensor regulates air temperature
based on sun load and also turns on your
headlamps. For more information on the solar
sensor, see “Sensors” later in this section.
To avoid blowing cold air in cold weather, the
system will delay turning on the fan until warm air
is available. The length of delay depends on
the engine coolant temperature. Pressing the fan
switch will override this delay and change the
fan to a selected speed.O(On/Off):Press this button to turn off the
climate control system. Outside air will still enter the
vehicle, and will be directed to the oor. This
direction can be changed by pressing the mode
button. Recirculation can be selected once you
have selected vent or bi-level mode. The
temperature can also be adjusted using either
temperature button. If you adjust the air delivery
mode or temperature settings with the system off,
the display will illuminate briey to show you the
settings and then return to off. Press the on/off
button or the up down arrows on the fan switch, the
defrost button, AUTO button, or the air conditioning
button to turn the system on when it is off.
Manual Operation
You may manually adjust the air delivery mode or
fan speed.
y9 z(Fan):The buttons with the fan symbols
allow you to manually adjust the fan speed.
Press the up arrow to increase fan speed and the
down arrow to decrease fan speed.
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StabiliTrak®Indicator Light
If equipped, this warning
light should come on
briey when the engine
is started.
If the warning light does not come on then, have it
xed so it will be ready to warn you if there is a
problem. If it stays on, or comes on when you are
driving, there may be a problem with your
StabiliTrak
®system and your vehicle may need
service. When this warning light is on, the system
is off and will not limit wheel spin. Adjust your
driving accordingly.
This light will also ash when the StabiliTrak
®
system is active.
If the StabiliTrak
®system warning light comes on
and stays on for an extended period of time
when the system is turned on, your vehicle needs
service. SeeStabiliTrak
®System on page 381
for more information.
Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your
vehicle is working. During a majority of the
operation, the gage will read 210°F (100°C) or
less. If you are pulling a load or going up hills, it is
normal for the temperature to uctuate and go
over the 235°F (113°C) mark. However, if the gage
reaches the 260°F (125°C) mark, it indicates
that the cooling system is working beyond
its capacity.
SeeEngine Overheating on page 516.
United StatesCanada
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