2006 GMC SIERRA cooling

Cold Weather Operation
(Allison Transmission®)
On cold days, approximately 32°F (0°C) or colder, your
automatic transmission is designed to shift differently.
The transmission uses a warm-up mode shift schedule
until the engine reaches normal operating temperature.
While the transmission is in warm-up mode it is normal for
transmission upshifts to be delayed or held longer. This
feature improves heater performance by giving quicker
vehicle warm-ups.
When temperatures are below−13°F (−25°C), the
transmission will prevent certain operations to protect
against damage. When active the DIC will display
the message “Trans in Warm-up”.
SeeDIC Warnings and Messages on page 3-55for
more information.
Tow/Haul Mode
If your vehicle has an automatic transmission, it may
have a Tow/Haul mode. If your vehicle has an
Allison Transmission
®see “Tow/Haul Mode (Allison
Transmission®) following. 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 Turn 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.
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SeeTow/Haul Mode Light on page 3-50for more
information.
If your vehicle is equipped with the Performance
Package-Enhanced Towing, activating the manual
selectable ride will adjust the shock absorber
characteristics to enhance the ride and handling of the
vehicle for towing or hauling heavy loads.
Also see Tow Haul Mode underTowing a Trailer on
page 4-67for more information.
Tow/Haul Mode
(Allison Transmission®)
If your vehicle has an Allison Transmission®,itmay
have a Tow/Haul mode. 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 Turn 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 3-50for more
information.
Also see “Tow Haul Mode” underTowing a Trailer on
page 4-67for more information.
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1(Defrost):This setting directs most air through
the windshield defroster outlets, side window defroster
outlets and some through the oor outlets.
Dual Climate Control System
With this system you can control the heating, cooling
and ventilation for your vehicle.
Fan Control
9(Fan):Turn the left knob clockwise or
counterclockwise to increase or decrease the fan speed.
Turn the knob to the off position to turn off the fan. If the
knob is in off, outside air will still enter the vehicle and will
be directed based on the position of the mode knob. The
temperature can also be adjusted using the temperature
levers.Turn the right knob clockwise or counterclockwise to
direct the airow inside of your vehicle.
Mode Control
To change the current mode, select one of the following:
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; then directs most of the
remaining air to the oor outlets. A little air is directed
toward the windshield and the side window outlets.
Cooler air is directed to the upper outlets and warmer
air to the oor outlets.
6(Floor):This mode directs most of the air to the
oor outlets with a little air directed to the windshield
and the side window outlets.
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Dual Automatic Climate Control
System
With this system, you can control the heating, cooling
and ventilation in your vehicle. Your 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.
Driver’s Side Temperature Knob
The driver’s side knob is used to adjust the temperature
of the air coming through the system on the driver’s side.
The temperature can be adjusted even if the system is
turned off. This is possible since outside air will always
ow through the system as the vehicle is moving forward
unless it is set to recirculation mode. See “Recirculation”
later in this section.Turn the knob counterclockwise or clockwise to lower
or increase the cabin temperature. The display will show
the temperature setting decreasing or increasing and
an arrow pointing to the driver will be displayed
under and to the left of the temperature setting.
Passenger’s Side Temperature Knob
The passenger’s side knob can be used to change the
temperature of the air coming through the system on the
passenger’s side of the vehicle. The temperature can be
adjusted even if the system is turned off. This is possible
since outside air will always ow through the system as
the vehicle is moving forward unless it is set to
recirculation mode. See “Recirculation” later in this
section.
Turn the knob counterclockwise or clockwise to lower or
increase the cabin temperature. The display will show
the temperature setting decreasing or increasing and an
arrow pointing to the passenger will be displayed under
and to the right of the temperature setting.
The passenger’s temperature setting can be set to match
the driver’s temperature setting by pressing and holding
the AUTO button for four seconds. Both the driver and
passenger arrows will be displayed.
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Automatic Operation
AUTO (Automatic):When automatic operation is
active the system will control the inside temperature,
the air delivery, and the fan speed.
Use the steps below to place the entire system in
automatic mode:
1. Press the AUTO button.
When AUTO is selected, the display will change to
show the current driver’s set temperature, delivery
mode and fan speed. Press the AUTO button again
within ve seconds to display the passenger’s set
temperature.
If the driver and passenger’s temperature settings
are not the same, the opposite side temperature
setting will be displayed for an additional
ve seconds. To make the passenger’s
temperature the same as the driver’s press and
hold the AUTO button for about four seconds.
When AUTO is selected, the air conditioning
operation and air inlet will be automatically
controlled. The air conditioning compressor will
run when the outside temperature is over about
40°F (4°C). The air inlet will normally be set to
outside air. If it’s hot outside, the air inlet may
automatically switch to recirculate inside air to help
quickly cool down your vehicle. The light on the
button will illuminate in recirculation.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. Turn the driver’s or
passenger’s side temperature knob 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 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.
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.
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Traction Off Light
If you have the Traction
Assist System, this light
should come on briey
when you turn the ignition
to RUN.
If the light does not come on then, the system may
require service; have it xed so it will be there to warn
you if the system is turned off.
If the light stays on, or comes on when you are driving,
there may be a problem with your Traction Assist System
and your vehicle may need service. When this light is on,
the system will not limit wheel spin. Adjust your driving
accordingly.
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 approach the 250°F (122°C) mark. 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 5-37.
United StatesCanada
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DRIVER DOOR AJAR
If the driver’s door is not fully closed, this message will
appear on the display and you will hear a chime. Stop
and turn off the vehicle, check the door for obstacles and
close the door again. Check to see if the message still
appears on the DIC. Pressing any of the four DIC buttons
will acknowledge the message and clear it from the DIC
display. If your vehicle does not have the four DIC
buttons, pressing the trip odometer reset stem will
acknowledge the message and clear it from the DIC
display.
ENGINE COOLANT HOT
If the cooling system temperature gets hot, this message
will appear in the DIC. Turn off the air conditioning. If the
message is still on, or if the engine coolant temperature
gage continues to rise, pull the vehicle over when it is
safe to do so. SeeEngine Coolant Temperature Gage on
page 3-43for more information. Stop the vehicle and
let the engine idle in PARK (P) for a few minutes, or
NEUTRAL with the parking brake set for manual
transmissions, to allow the coolant to reach a safe
temperature. This message will clear when the coolant
temperature drops to safe operating temperature.
ENGINE OVERHEATED
Notice:If you drive your vehicle while the engine is
overheating, severe engine damage may occur. If an
overheat warning appears on the instrument panel
cluster and/or DIC, stop the vehicle as soon as
possible. Do not increase the engine speed above
normal idling speed. SeeEngine Overheating on
page 5-37for more information.
If the engine cooling system reaches unsafe
temperatures for operation, this message will appear in
the DIC and you will hear a chime. Stop and turn off the
vehicle as soon as it is safe to do so to avoid severe
damage. This message will clear when the engine has
cooled to a safe operating temperature.
FUEL LEVEL LOW
If the fuel level is low, this message will appear on the
DIC and you will hear a chime. Refuel as soon as
possible. Pressing any of the four DIC buttons will
acknowledge the message and clear it from the DIC
display. If your vehicle does not have the four DIC
buttons, pressing the trip odometer reset stem will
acknowledge the message and clear it from the DIC
display. SeeLow Fuel Warning Light on page 3-51,
Fuel Gage on page 3-51, andFuel on page 5-5.
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KEYFOB X BATTERY LOW
If a remote keyless entry transmitter battery is low, this
message will appear on the DIC. The battery needs to be
replaced in the transmitter. See “Battery Replacement”
underRemote Keyless Entry System Operation on
page 2-5. Pressing any of the four DIC buttons will
acknowledge the message and clear it from the DIC
display. If your vehicle does not have the four DIC
buttons, pressing the trip odometer reset stem will
acknowledge the message and clear it from the
DIC display.
LEFT REAR DOOR AJAR (Crew Cab)
If the driver’s side rear door is not fully closed, this
message will appear on the display and you will hear a
chime. Stop and turn off the vehicle, check the door for
obstacles and close the door again. Check to see if the
message still appears on the DIC. Pressing any of the
four DIC buttons will acknowledge the message and clear
it from the DIC display. If your vehicle does not have the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
LOW COOLANT LEVEL
Notice:Engine damage from running your engine
without coolant is not covered by your warranty. See
“Overheated Engine Protection Operating Mode”
in the Index for information on driving to a safe
place in an emergency.
If your vehicle has a low coolant level sensor, this
message will appear on the DIC if the engine coolant
level is low. Adding coolant to the coolant recovery
tank will clear the message. SeeCooling System on
page 5-40. Pressing any of the four DIC buttons will
acknowledge the message and clear it from the DIC
display. If your vehicle does not have the four DIC
buttons, pressing the trip odometer reset stem will
acknowledge the message and clear it from the
DIC display.
OIL LIFE RESET
This message will appear on the display for about
10 seconds after resetting the change engine oil
message. See “Engine Oil Life System” underDIC
Operation and Displays on page 3-53andEngine Oil
(Gasoline Engine) on page 5-20for more information.
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