reset GMC SIERRA 2008 Owner's Manual

operates. Before adding electrical equipment, check
with your dealer/retailer. If you do not, your engine
might not perform properly. Any resulting damage
would not be covered by your vehicle’s warranty.
Fast Idle System
Fast Idle System with Switch
If your vehicle has this
feature it is available only
with cruise control. The
manual fast idle switch is
operated using the
cruise control buttons
located on the left hand
side of the steering wheel.
This system can be used to increase your engine idle
speed whenever the following conditions are met:
The park brake is set.
The brake pedal is not pressed.
The vehicle must not be moving and the accelerator
must not be pressed.To control the fast idle:
To Enable the Fast idle, press and release the
Cruise Control On/Off button and ensure that
the LED is lit.
For the preset Fast Idle, press and release the
cruise set switch. This will set the preset fast
idle speed.
For the variable fast idle, press and hold the
accelerator at the desired RPM, then press
and release the cruise control cruise set switch to
set the desired idle speed.
When the fast idle is active the Driver Information
Center (DIC) will display “FAST IDLE ON”.
One of the following actions will turn off the fast idle:
Pressing the brake.
Selecting the Cancel button.
Releasing the Parking Brake.
The transmission shifter is moved out of PARK (P)
or NEUTRAL (N).
Selecting the cruise control on/off button when it
was previously on.
2-25

Outside Power Foldaway Mirrors
If your vehicle is equipped
with outside power
foldaway mirrors, the
controls are located on the
driver’s door armrest.
Press (A) to select the driver’s side mirror. Then
press the arrows located on the four-way control
pad to adjust the mirror. Press (A) again to deselect
the mirror.
Press (B) to select the passenger’s side mirror.
Then press the arrows located on the four-way
control pad to adjust the mirror. Press (B) again to
deselect the mirror.
Press (C) to fold the mirrors out to the driving
position.
Press (D) to fold the mirrors in to the folded
position.If the mirrors are accidentally folded/unfolded manually,
they may shake or utter at normal driving speeds
and may not stay in the unfolded position. If this
happens, you will need to reset the mirrors. See
“Resetting the Power Foldaway Mirrors” next.
Resetting the Power Foldaway Mirrors
You will need to reset the power foldaway mirrors if the
following occurs:
The mirrors are accidentally obstructed while
folding.
They are accidentally manually folded/unfolded.
The mirrors will not stay in the unfolded position.
The mirrors shake and utter at normal driving
speeds.
To reset the power foldaway mirrors, fold and unfold
them one time using the mirror controls. This will reset
them to their normal position.
This mirror has the following features.
Automatic Dimming
The driver’s outside mirror will adjust for the glare of the
headlamps behind you. SeeAutomatic Dimming
Rearview Mirror with OnStar
®, Compass and
Temperature Display on page 2-55.
2-61

The rainsensor will automatically control the frequency of
the wipes from the off setting to the high speed setting
according to the weather conditions. The wipers can be
left in a rainsense mode even when it is not raining.
When Rainsense™ is active, the headlamps will turn on
automatically if the exterior lamp control is in the
AUTO position and the wipers are active.
Notice:Going through an automatic car wash with
the wipers on can damage them. Turn the wipers
off when going through an automatic car wash.
Windshield Washer
{CAUTION:
In freezing weather, do not use your washer
until the windshield is warmed. Otherwise the
washer uid can form ice on the windshield,
blocking your vision.
L(Washer Fluid):Push the paddle marked with the
windshield washer symbol at the top of the multifunction
lever, to spray washer uid on the windshield. The
wipers clear the window and then either stop or return
to the preset speed.
Heated Windshield Washer
For vehicles with the heated windshield washer uid
system it can be used to help clear ice, snow, tree sap,
or bugs from your windshield.
The button is located in
the switchbank under the
climate controls.
Push the heated washer uid button to activate the
heated windshield washer uid system. The indicator
light will ash. This activation initiates four heated
wash/wipe cycles. The rst heated wash/wipe cycle may
take up to 40 seconds to occur, depending on outside
temperature. After the rst wash/wipe cycle, it may take
up to 20 seconds for each of the remaining cycles to
begin. Press the button again to turn off the heated
windshield washer uid system or it will automatically
turn off after four wipe cycles have been completed.
When the heated windshield washer uid system
is activated under certain outside temperature
conditions, steam may ow out of the washer nozzles
for a short period of time before washer uid is sprayed.
This is a normal condition.
3-13

Resuming a Set Speed
If you apply the brakes while the cruise control is set,
the cruise control is disengaged. But it does not need to
be reset.
Once the vehicle speed reaches about 25 mph
(40 km/h) or more, press the +RES button on the
steering wheel. The vehicle will go back to the previous
set speed and stay there.
Increasing Speed While Using Cruise
Control
To increase the cruise speed while using cruise control:
Press and hold the +RES button on the steering
wheel until you reach your new desired speed,
then release it.
To increase vehicle speed in small increments,
press the +RES button. Each time this is done,
the vehicle will go about 1 mph (1.6 km/h) faster.
Reducing Speed While Using Cruise
Control
To reduce the vehicle speed while using cruise control:
Press and hold the SET– button on the steering
wheel until the desired lower speed is reached,
then release it.
To slow down in very small amounts, press the
SET– button on the steering wheel briey. Each
time this is done, the vehicle will go about 1 mph
(1.6 km/h) slower.
Passing Another Vehicle While Using
Cruise Control
Use the accelerator pedal to increase the vehicle speed.
When you take your foot off the pedal, the vehicle will
slow down to the previous set cruise speed.
Using Cruise Control on Hills
How well the cruise control will work on hills depends
upon the vehicle speed, load, and the steepness of the
hills. While going up steep hills, you might have to
step on the accelerator pedal to maintain the vehicle’s
speed. While going downhill, you might have to brake or
shift to a lower gear to keep the vehicle’s speed
down. Of course, applying the brake turns off the cruise
control. Many drivers nd this to be too much trouble
and do not use cruise control on steep hills.
Ending Cruise Control
There are three ways to end cruise control:
Step lightly on the brake pedal.
Press the cancel button on the steering wheel.
Press the On/Off button on the steering wheel.
3-16

Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your vehicle has
been driven, in either miles (used in the United States)
or kilometers (used in Canada).
Engine Hour Meter Display
The Driver Information Center (DIC) can also display
the number of hours the engine has run. To display the
engine hours, turn the ignition off, press and hold the
reset button for at least four seconds. The hour
meter will be displayed for up to 30 seconds, or until the
ignition is turned on. SeeDIC Operation and Displays
(With DIC Buttons) on page 3-55orDIC Operation
and Displays (Without DIC Buttons) on page 3-60for
more information.
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
Press the reset button, located on the instrument panel
cluster next to the voltmeter, to toggle between the
trip odometer and the regular odometer. Holding
the reset button for approximately one second while the
trip odometer is displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
SeeDIC Operation and Displays (With DIC Buttons) on
page 3-55orDIC Operation and Displays (Without
DIC Buttons) on page 3-60for more information.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm). See “Grade Braking
(Allison Transmission
®)” underTow/Haul Mode on
page 2-34for more information.
3-36

This light should come on briey when you turn the
ignition key to RUN. If it does not come on then, have it
xed so it will be ready to warn you if there is a
problem.
{CAUTION:
Your brake system may not be working properly
if the brake system warning light is on. Driving
with the brake system warning light on can lead
to an accident. If the light is still on after you
have pulled off the road and stopped carefully,
have the vehicle towed for service.
If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push or may go closer to the oor. It may
take longer to stop. If the light is still on, have the vehicle
towed for service. SeeTowing Your Vehicle on
page 4-50.
Antilock Brake System Warning
Light
For vehicles with the
Antilock Brake System
(ABS), this light will come
on briey when you
start the engine.
That is normal. If the light does not come on then, have it
xed so it will be ready to warn you if there is a problem.
If the ABS light stays on, turn the ignition off, if the light
comes on when you are driving, stop as soon as it
is safely possible and turn the ignition off. Then start the
engine again to reset the system. If the ABS light still
stays on, or comes on again while you are driving, your
vehicle needs service. If the regular brake system
warning light is not on, you still have brakes, but you do
not have antilock brakes. If the regular brake system
warning light is also on, you do not have antilock brakes
and there is a problem with your regular brakes. See
Brake System Warning Light on page 3-44
For vehicles with a Driver Information Center (DIC), see
DIC Warnings and Messages on page 3-63for all
brake related DIC messages.
3-45

DIC Operation and Displays (With
DIC Buttons)
If your vehicle has DIC buttons, the information below
explains the operation of this system.
The DIC has different displays which can be accessed
by pressing the DIC buttons located on the instrument
panel, next to the steering wheel.
The DIC displays trip, fuel, and vehicle system
information, and warning messages if a system problem
is detected.
The DIC also allows some features to be customized.
SeeDIC Vehicle Customization (With DIC Buttons)
on page 3-72for more information.
If your vehicle has DIC buttons, you can also use the
trip odometer reset stem to view some of the DIC
displays. See “DIC Operation and Displays (Without DIC
Buttons)” later in this section.
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, and transmission temperature.
Some vehicles also display instantaneous economy and
an Active Fuel Management™ indicator.
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, and Remote Keyless Entry (RKE)
transmitter programming.
3-55

U(Customization):Press this button to customize the
feature settings on your vehicle. SeeDIC Vehicle
Customization (With DIC Buttons) on page 3-72for 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.
Trip Odometer
Press the trip/fuel button until TRIP displays. This
display shows the current distance traveled in either
miles (mi) or kilometers (km) since the last reset for the
trip odometer. Pressing the trip odometer reset stem
will also display the trip odometer.
The trip odometer can be reset to zero by pressing the
set/reset button while the trip odometer is displayed.
You can also reset the trip odometer while it is displayed
by pressing and holding the trip odometer reset stem.
The trip odometer has a feature called the retro-active
reset. This can be used to set the trip odometer to
the number of miles (kilometers) driven since the ignition
was last turned on. This can be used if the trip
odometer is not reset at the beginning of the trip.
To use the retro-active reset feature, press and hold the
set/reset button for at least four seconds. The trip
odometer will display the number of miles (mi) or
kilometers (km) driven since the ignition was last turned
on and the vehicle was moving. Once the vehicle
begins moving, the trip odometer will accumulate
mileage. For example, if the vehicle was driven 5 miles
(8 km) before it is started again, and then the
retro-active reset feature is activated, the display will
show 5 miles (8 km). As the vehicle begins moving, the
display will then increase to 5.1 miles (8.2 km),
5.2 miles (8.4 km), etc.
3-56

Fuel Range
Press the trip/fuel button until FUEL RANGE displays.
This display shows the approximate number of
remaining miles (mi) or kilometers (km) the vehicle can
be driven without refueling. The display will show
LOW if the fuel level is low.
The fuel range estimate is based on an average of the
vehicle’s fuel economy over recent driving history
and the amount of fuel remaining in the fuel tank. This
estimate will change if driving conditions change.
For example, if driving in traffic and making frequent
stops, this display may read one number, but if
the vehicle is driven on a freeway, the number may
change even though the same amount of fuel is in the
fuel tank. This is because different driving conditions
produce different fuel economies. Generally, freeway
driving produces better fuel economy than city driving.
Fuel range cannot be reset.
Average Economy
Press the trip/fuel button until AVG ECONOMY displays.
This display shows the approximate average miles
per gallon (mpg) or liters per 100 kilometers (L/100 km).
This number is calculated based on the number of
mpg (L/100 km) recorded since the last time this menu
item was reset. To reset AVG ECONOMY, press
and hold the set/reset button.
Fuel Used
Press the trip/fuel button until FUEL USED displays.
This display shows the number of gallons (gal) or
liters (L) of fuel used since the last reset of this menu
item. To reset the fuel used information, press and hold
the set/reset button while FUEL USED is displayed.
Timer
Press the trip/fuel button until TIMER displays. This
display can be used as a timer.
To start the timer, press the set/reset button while
TIMER is displayed. The display will show the amount
of time that has passed since the timer was last
reset, not including time the ignition is off. Time will
continue to be counted as long as the ignition is
on, even if another display is being shown on the DIC.
The timer will record up to 99 hours, 59 minutes
and 59 seconds (99:59:59) after which the display will
return to zero.
To stop the timer, press the set/reset button briey while
TIMER is displayed.
To reset the timer to zero, press and hold the set/reset
button while TIMER is displayed.
3-57

Transmission Temperature
Press the trip/fuel button until TRANS TEMP displays.
This display shows the temperature of the automatic
transmission uid in either degrees Fahrenheit (°F) or
degrees Celsius (°C).
Instantaneous Economy and Active Fuel
Management™ Indicator
If your vehicle has this display, press the trip/fuel button
until INST ECONOMY V8 MODE displays. This
display shows the current fuel economy at a particular
moment and will change frequently as driving conditions
change. This display shows the instantaneous fuel
economy in miles per gallon (mpg) or liters per
100 kilometers (L/100 km). Unlike average economy,
this screen cannot be reset.
An Active Fuel Management™ indicator will display on
the right side of the DIC, while INST ECONOMY
displays on the left side. Active Fuel Management™
allows the engine to operate on either four or eight
cylinders, depending on your driving demands. When
Active Fuel Management™ is active, V4 MODE will
display on the DIC. When Active Fuel Management™ is
inactive, V8 MODE will display. SeeActive Fuel
Management™ on page 2-27for more information.
Blank Display
This display shows no information.
Vehicle Information Menu Items
T
(Vehicle Information):Press this button to scroll
through the following menu items:
Oil Life
Press the vehicle information button until OIL LIFE
REMAINING displays. This display shows an estimate
of the oil’s remaining useful life. If you see 99% OIL LIFE
REMAINING on the display, that means 99% of the
current oil life remains. The engine oil life system
will alert you to change the oil on a schedule consistent
with your driving conditions.
When the remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear on the display.
See “CHANGE ENGINE OIL SOON” underDIC
Warnings and Messages on page 3-63. You should
change the oil as soon as you can. SeeEngine
Oil (Gasoline Engine) on page 5-15. In addition to the
engine oil life system monitoring the oil life, additional
maintenance is recommended in the Maintenance
Schedule in this manual. SeeScheduled Maintenance
(Gasoline Engine) on page 6-4for more information.
Remember, you must reset the OIL LIFE display
yourself after each oil change. It will not reset itself.
3-58