2008 GMC SIERRA lights

Shifting into NEUTRAL
To shift the transfer case to NEUTRAL do the following:
1. Make sure the vehicle is parked so that it will not roll.
2. Set the parking brake and press and hold the
regular brake pedal. SeeParking Brake on
page 2-49for more information.
3. Start the vehicle or turn the ignition to ON/RUN.
4. Shift the transmission to NEUTRAL (N).
5. Shift the transfer case to Two-Wheel-Drive High.
6. Turn the transfer case dial clockwise to NEUTRAL
till it stops and hold it for 10 seconds. Then slowly
release the dial to the four low position. The
NEUTRAL light will come on when the transfer case
shift to NEUTRAL is complete.
7. If the engine is running, verify that the transfer case
is in NEUTRAL (N) by shifting the transmission to
REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second.
8. Turn the ignition to ACC/ACCESSORY, which will
turn the engine off.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to moving
the vehicle.
11. Turn the ignition to LOCK/OFF.
Shifting Out of NEUTRAL
To shift out of NEUTRAL do the following:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Turn the transfer case dial to Two-Wheel-Drive High.
After the transfer case has shifted out of NEUTRAL
the NEUTRAL light will go out.
4. Release the parking brake prior to moving the
vehicle.
Notice:Shifting the transmission into gear before
the requested mode indicator light has stopped
ashing could damage the transfer case. To
help avoid damaging your vehicle, always wait for
the mode indicator lights to stop ashing before
shifting the transmission into gear.
5. Start the engine and shift the transmission to the
desired position.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to enter the
shift protection mode. This will protect the transfer case
from possible damage and will only allow the transfer
case to respond to one shift per 10 seconds. The transfer
case may stay in this mode for up to three minutes.
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Automatic Transfer Case
The transfer case knob
is located next to the
steering column.
For information on StabiliTrak
®, seeStabiliTrak®
System on page 4-6.
Use the dial to shift into and out of Four-Wheel Drive.
You can choose among ve driving settings:
Indicator lights in the dial show which setting you are in.
The indicator lights will come on briey when you turn
on the ignition and one will stay on. If the lights do
not come on, you should take your vehicle to your dealer
for service. An indicator light will ash while shifting
the transfer case. It will remain illuminated when the shift
is complete. If for some reason the transfer case
cannot make a requested shift, it will return to the last
chosen setting.2
m(Two-Wheel-Drive High):This setting is used for
driving in most street and highway situations. The
front axle is not engaged in Two-Wheel Drive. This
setting also provides the best fuel economy.
AUTO (Automatic Four-Wheel Drive):This setting is
ideal for use when road surface traction conditions are
variable. When driving your vehicle in AUTO, the front
axle is engaged, but the vehicle’s power is sent only to
the front and rear wheels automatically based on driving
conditions. Driving in this mode results in slightly lower
fuel economy than Two-Wheel-Drive High.
4
m(Four-Wheel-Drive High):Use the
Four-Wheel-Drive High position when extra traction is
needed, such as on snowy or icy roads or in most
off-road situations. This setting also engages the front
axle to help drive your vehicle. This is the best setting to
use when plowing snow.
4
n(Four-Wheel-Drive Low):This setting also
engages the front axle and delivers extra torque. You
may never need this setting. It sends maximum power to
all four wheels. You might choose Four-Wheel-Drive
Low if you are driving off-road in deep sand, deep mud,
deep snow, and while climbing or descending steep
hills. StabiliTrak
®will not engage in this mode.
SeeStabiliTrak®System on page 4-6for more
information.
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Notice:Shifting the transmission into gear before
the requested mode indicator light has stopped
ashing could damage the transfer case. To
help avoid damaging your vehicle, always wait for
the mode indicator lights to stop ashing before
shifting the transmission into gear.
It is typical for your vehicle to exhibit signicant
engagement noise and bump when shifting between
Four-Wheel-Drive Low and Four-Wheel-Drive High
ranges or from NEUTRAL with the engine running.
If the knob is turned to the Four-Wheel-Drive Low
position when your vehicle is in gear and/or moving, the
Four-Wheel-Drive Low indicator light will ash for
30 seconds and not complete the shift unless your
vehicle is moving less than 3 mph (5 km/h) and the
transmission is in NEUTRAL (N). After 30 seconds the
transfer case will shift to Four-Wheel-Drive High mode.
Shifting Out of Four-Wheel-Drive Low
To shift from Four-Wheel-Drive Low to Four-Wheel-Drive
High, AUTO or Two-Wheel-Drive High, your vehicle
must be stopped or moving less than 3 mph (5 km/h)
with the transmission in NEUTRAL (N) and the ignition in
RUN. The preferred method for shifting out of
Four-Wheel-Drive Low is to have your vehicle moving1 to 2 mph (1.6 to 3.2 km/h). Turn the knob to the
Four-Wheel-Drive High, AUTO or Two-Wheel-Drive High
position. You must wait for the Four-Wheel-Drive
High, AUTO or Two-Wheel-Drive High indicator light to
stop ashing and remain on before shifting your
transmission into gear.
Notice:Shifting the transmission into gear before
the requested mode indicator light has stopped
ashing could damage the transfer case. To
help avoid damaging your vehicle, always wait for
the mode indicator lights to stop ashing before
shifting the transmission into gear.
It is typical for your vehicle to exhibit signicant
engagement noise and bump when shifting between
Four-Wheel-Drive Low and Four-Wheel-Drive High
ranges or from NEUTRAL with the engine running.
If the knob is turned to the Four-Wheel-Drive High,
AUTO, or Two-Wheel-Drive High switch position when
your vehicle is in gear and/or moving, the
Four-Wheel-Drive High, AUTO or Two-Wheel-Drive High
indicator light will ash for 30 seconds but will not
complete the shift unless your vehicle is moving less
than 3 mph (5 km/h) and the transmission is in
NEUTRAL (N).
2-47

Shifting into NEUTRAL
To shift the transfer case to NEUTRAL do the following:
1. Make sure the vehicle is parked so that it will not roll.
2. Set the parking brake and apply the regular brake
pedal. SeeParking Brake on page 2-49for more
information.
3. Start the vehicle or turn the ignition to ON/RUN.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to Two-Wheel Drive High.
6. Turn the transfer case dial clockwise to NEUTRAL
till it stops and hold it for 10 seconds. Then slowly
release the dial to the four low position. The
NEUTRAL light will come on when the transfer case
shift to NEUTRAL is complete.
7. If the engine is running, make sure that the transfer
case is in NEUTRAL (N) by shifting the transmission
to REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second.
8. Turn the ignition to ACC/ACCESSORY, which will
turn the engine off.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to moving
the vehicle.
11. Turn the ignition to LOCK/OFF.
Shifting Out of NEUTRAL
To shift out of NEUTRAL do the following:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Turn the transfer case dial to Two-Wheel-Drive
High, Four-Wheel-Drive High, AUTO.
After the transfer case has shifted out of NEUTRAL
the NEUTRAL light will go out.
4. Release the parking brake prior to moving the
vehicle.
Notice:Shifting the transmission into gear before
the requested mode indicator light has stopped
ashing could damage the transfer case. To
help avoid damaging your vehicle, always wait for
the mode indicator lights to stop ashing before
shifting the transmission into gear.
5. Start the engine and shift the transmission to the
desired position.
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Follow the proper steps to be sure your vehicle will not
move. SeeShifting Into PARK (P) on page 2-50.
If you are pulling a trailer, seeTowing a Trailer on
page 4-55.
Mirrors
Manual Rearview Mirror
When you are sitting in a comfortable driving position,
adjust the mirror so you can see clearly behind your
vehicle. Hold the mirror in the center to move it up or
down and side to side. The day/night adjustment allows
you to adjust the mirror to avoid glare from the lamps
behind you. Push the tab forward for daytime use
and pull it for nighttime use.
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, the
automatic dimming mirror dims to the proper level to
minimize glare from lights behind you after dark.
The mirror has a dual display in the upper right corner
of the mirror face that shows the compass reading
and the outside temperature.Control buttons for the OnStar
®system are at the
bottom of the mirror. SeeOnStar®System on page 2-65
for more information about the services OnStar®
provides.
P(On/Off):This is the on/off button.
Temperature and Compass Display
Press the on/off button, located to the far left, briey to
turn the compass/temperature display on or off.
If the display reads CAL, the compass needs to be
calibrated. For more information, see “Compass
Calibration” following.
To adjust between Fahrenheit and Celsius:
1. Press and hold the on/off button for approximately
four seconds until either a ashing F or C appears.
2. Press the button again to change the display to the
desired unit of measurement. After approximately
four seconds of inactivity, the new unit will be locked
in and the compass/temperature display will
return.
If an abnormal temperature reading is displayed for an
extended period of time, see your dealer/retailer.
Under certain circumstances, a delay in updating the
temperature is normal.
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2. Press and hold the on/off button until a Z and a
zone number appears in the display. The compass
is now in zone mode.
3. Keep pressing the on/off button until the desired
zone number appears in the display. Release the
button. After approximately four seconds of
inactivity, the new zone number will be locked in
and the compass/temperature display will return.
Cleaning the Mirror
When cleaning the mirror, use a paper towel or similar
material dampened with glass cleaner. Do not spray
glass cleaner directly on the mirror as that may cause
the liquid cleaner to enter the mirror housing.
Automatic Dimming Rearview Mirror
with Compass and Temperature
Display
Your vehicle may have this mirror. When on, an
automatic dimming mirror will dim to the proper level to
minimize glare from lights behind you after dark.
The mirror also includes a dual display in the upper
right corner of the mirror with the compass reading and
the outside temperature.
Yb:Briey press this button to turn the display on
or off.
2-57

Object Detection Systems
Ultrasonic Rear Parking
Assist (URPA)
If your vehicle has the Ultrasonic Rear Parking Assist
(URPA) system, it helps you park easier and avoid other
vehicles while in REVERSE (R). It operates at speeds
less than 5 mph (8 km/h). It can determine how close
objects are to the rear bumper, up to 8 feet (2.5 m)
behind your vehicle. The distance sensors are located
on the rear bumper.
{CAUTION:
The Ultrasonic Rear Parking Assist (URPA)
system does not replace driver vision.
It cannot detect:
objects that are below the bumper,
underneath the vehicle, or if they are too
close or far from the vehicle
children, pedestrians, bicyclists, or pets.
CAUTION: (Continued)
CAUTION: (Continued)
If you do not use proper care before and while
backing; vehicle damage, injury, or death
could occur. Even with URPA, always check
behind your vehicle before backing up. While
backing, be sure to look for objects and check
your vehicle’s mirrors.
On some vehicles this
display is located near
the passenger side
rear window and can be
seen by looking over
your right shoulder.
If your vehicle has the display, there are three
color-coded lights to provide distance and system
information.
If your vehicle does not have the display and it has
URPA, you will hear the beeps as described in the
following information.
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How the System Works
URPA comes on automatically when the shift lever is
moved into REVERSE (R). The rear display will
then briey illuminate to let you know the system is
working.
URPA operates only at speeds less than 5 mph
(8 km/h). If you are above this speed, the red light on
the rear display will ash.
To be detected, objects must be at least 10 inches
(25.4 cm) off the ground and below tailgate level.
Objects must also be within 8 feet (2.5 m) from your
rear bumper. This distance may be less during warmer
or humid weather.
A single beep will sound the rst time an object is
detected between 20 inches (0.5 m) and 8 feet (2.5 m)
away. Beeping will occur for three seconds when
you are closer than 1 foot (0.3 m) from the object.The following describes what will occur with the URPA
display as you get closer to a detected object:
Description English Metric
amber light 8 ft 2.5 m
amber/amber lights 40 in 1.0 m
amber/amber/red lights 23 in 0.6 m
amber/amber/red lights
ashing and beep for
three seconds1 ft 0.3 m
The system can be
disabled by pressing the
rear park aid disable button
located next to the radio.
The indicator light will
come on to indicate that
URPA is off.
Notice:If you use URPA while the tailgate is
lowered, it may not detect an object behind your
vehicle, and you might back into the object and
damage your vehicle. Always verify the tailgate is
closed when using URPA or turn off URPA when
driving with the tailgate lowered.
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