2007 GMC SIERRA CLASSIC trailer

6. You may 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 mode protects the transfer case
from possible damage and only allows
the transfer case to respond to one shift per
10 seconds. The transfer case may stay in this
mode for up to three minutes.
7. After the transfer case has shifted out of
NEUTRAL the red light will go out.
Parking Brake
To set the parking brake, hold the regular brake
pedal down with your right foot. Push down
the parking brake pedal with your left foot.
A chime will activate and the warning light will
ash when the parking brake is applied and
the vehicle is moving at least 3 mph (5 km/h) for
at least three seconds.To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever,
located above the parking brake pedal, with the
parking brake symbol, to release the parking brake.
If the ignition is on when the parking brake is
released, the brake system warning light will go off.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Verify
that the parking brake is fully released and the
brake warning light is off before driving.
If you are towing a trailer and are parking on any
hill, seeTowing a Trailer on page 429.
169

Shifting Into Park (P)
(Automatic Transmission)
{CAUTION:
It can be dangerous to get out of your
vehicle if the shift lever is not fully in
PARK (P) with the parking brake rmly set.
Your vehicle can roll. If you have left the
engine running, the vehicle can move
suddenly. You or others could be injured.
To be sure your vehicle will not move, even
when you are on fairly level ground, use
the steps that follow. With four-wheel drive,
if your transfer case is in NEUTRAL, your
vehicle will be free to roll, even if your shift
lever is in PARK (P). So, be sure the
transfer case is in a drive gear — not in
NEUTRAL. If you are pulling a trailer, see
Towing a Trailer on page 429.1. Hold the brake pedal down with your right foot
and set the parking brake.
2. Move the shift lever into the PARK (P)
position by pulling the shift lever toward
you and moving it up as far as it will go.
3. If your vehicle has four-wheel drive, be sure
the transfer case is in a drive gear – not in
NEUTRAL.
4. Turn the ignition key to LOCK.
5. Remove the key and take it with you. If you
can leave your vehicle with the ignition key in
your hand, your vehicle is in PARK (P).
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{CAUTION:
Four-wheel drive vehicles with the transfer
case in NEUTRAL will allow the vehicle to
roll, even if your automatic transmission
shift lever is in PARK (P). So, be sure the
transfer case is in a drive gear — not in
NEUTRAL. Always set your parking brake.
Follow the proper steps to be sure your vehicle
will not move. SeeShifting Into Park (P)
(Automatic Transmission) on page 170.
If you are pulling a trailer, seeTowing a Trailer on
page 429.
Mirrors
Manual Rearview Mirror
Pull or push the tab under the inside rearview
mirror to adjust it to the night or daytime setting. In
the nighttime setting, the glare from headlamps
behind the vehicle will be less intense.
Automatic Dimming Rearview Mirror
with OnStar
®, Compass and
Temperature Display
Your vehicle may have this feature. When on, an
automatic dimming mirror automatically dims
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 face. The compass
reading and the outside temperature will both
appear in the display at the same time.
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, you will need to calibrate
the compass. For more information on calibration,
see below.
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Passenger Airbag Indicator
The mirror may be equipped with a passenger
airbag indicator on the mirror glass, just above the
buttons. If the vehicle has this feature the mirror
will display the word ON, or an airbag symbol
in Canada, when the passenger airbag is enabled.
For more information seePassenger Sensing
System on page 103
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.
Outside Manual Mirrors
Adjust your outside mirrors so you can just see
the side of your vehicle and have a clear view of
objects behind you. The mirrors can be folded
in to enter narrow areas.
The use of hood-mounted air deectors and
add-on convex mirror attachments may adversely
affect mirror performance.
Outside Trailer-Tow Mirrors
If your vehicle is equipped with this style
trailering-type mirror, they can be adjusted so you
can have a clear view of the objects behind you.
Pull out the mirror head to extend it for better
visibility when towing a trailer.
183

If your vehicle is
equipped with this style
trailering-type mirror,
they can be adjusted so
you can have a clear
view of the objects
behind you.
Adjust each mirror by turning it left or right. Once
the mirror is adjusted to the correct position,
tighten the set screw to hold the mirror in place.
These mirrors can also be manually folded in.
On the lower portion of the mirror is a convex
mirror. A convex mirror’s surface is curved so you
can see more from the driver’s seat.If your vehicle is equipped with this trailer towing
type mirror, they can be adjusted so you can
have a clear view of the objects behind you. Pull
out the mirror head to extend it for better
visibility when towing a trailer.
These mirrors can also be manually folded in.
On the lower portion of the mirror is a convex
mirror. A convex mirror’s surface is curved so you
can see more from the driver’s seat.
184

If the transmission continues to operate above
265°F (130°C), contact your nearest dealer or the
GM Roadside Assistance Center. SeeRoadside
Assistance Program on page 644.
Notice:If you drive your vehicle with the
transmission temperature gage above normal
operating range, you can damage the
transmission. This could lead to costly repairs
that would not be covered by your warranty.
Do not drive your vehicle while the
transmission temperature gage reading is
above normal. See your dealer for service.
The following situations can cause the
transmission to operate at higher temperatures:
Towing a trailer
Hot outside air temperatures
Hauling a large or heavy load
Low transmission uid level
High transmission uid level
Restricted air ow to the radiator and the
auxiliary transmission oil cooler, if equipped.A temporary solution to reduce hotter transmission
operating temperatures may be to let the
transmission cool down. If the transmission is
operated at higher temperatures on a frequent
basis, seeScheduled Maintenance (Gasoline
Engine) on page 617for the proper transmission
maintenance intervals.
Malfunction Indicator Lamp
Check Engine Light
Your vehicle has a
computer which
monitors operation of
the fuel, ignition,
and emission control
systems.
258

If the Light is Flashing
The following may prevent more serious damage
to your vehicle:
Reducing vehicle speed
Avoiding hard accelerations
Avoiding steep uphill grades
If you are towing a trailer, reduce the amount
of cargo being hauled as soon as it is
possible
If the light stops ashing and remains on steady,
see “If the Light Is On Steady” following.
If the light continues to ash, when it is safe to do
so, stop the vehicle. Find a safe place to park
your vehicle. Turn the key off, wait at least
10 seconds and restart the engine. If the light
remains on steady, see “If the Light Is On Steady”
following. If the light is still ashing, follow the
previous steps, and see your dealer for service as
soon as possible.
If the Light Is On Steady
You may be able to correct the emission system
malfunction by considering the following:
Did you recently put fuel into your vehicle?
If so, reinstall the fuel cap, making sure to fully
install the cap. SeeFilling the Tank on page 474.
The diagnostic system can determine if the
fuel cap has been left off or improperly installed.
A loose or missing fuel cap will allow fuel to
evaporate into the atmosphere. A few driving trips
with the cap properly installed should turn the
light off.
Did you just drive through a deep puddle of water?
If so, your electrical system may be wet. The
condition will usually be corrected when the
electrical system dries out. A few driving trips
should turn the light off.
260

TRANSMISSION HOT
Notice:If you drive your vehicle while the
transmission uid is overheating and the
transmission temperature warning is displayed
on the instrument panel cluster and/or DIC,
you can damage the transmission. This could
lead to costly repairs that would not be
covered by your warranty. Do not drive your
vehicle with overheated transmission uid
or while the transmission temperature warning
is displayed.
If the transmission uid temperature becomes
high, this message will appear on the DIC display.
When the transmission enters the protection
mode, you may notice a change in the
transmission shifting patterns. When the
transmission uid temperature returns to normal,
the display will turn off and the transmission
shifting patterns will return to normal.If the vehicle has the Tow/Haul mode, use this
feature if the transmission is operating at higher
temperatures and/or the following situations
exist, which can cause the transmission to operate
at higher temperatures:
Towing a trailer
Hot outside air temperatures
Hauling a large or heavy load
Over-loading
Low transmission uid level
High transmission uid level
Restricted air ow to the radiator and the
auxiliary transmission oil cooler
A temporary solution to hotter transmission
operating temperatures may be to let the
transmission cool down. If the transmission is
operated at higher temperatures on a frequent
basis, seeScheduled Maintenance (Gasoline
Engine) on page 617for the transmission
your vehicle is equipped with for the proper
transmission maintenance intervals. Also see
Transmission Temperature Gage on page 257for
more information.
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