2007 GMC SIERRA CLASSIC service indicator

If a person of adult-size is sitting in the right front
passenger’s seat, but the off indicator is lit, it could
be because that person is not sitting properly in the
seat. If this happens, turn the vehicle off and ask
the person to place the seatback in the fully upright
position, then sit upright in the seat, centered on the
seat cushion, with the person’s legs comfortably
extended. Restart the vehicle and have the person
remain in this position for about two minutes. This
will allow the system to detect that person and then
enable the right front passenger’s airbag.
{CAUTION:
If the airbag readiness light in the
instrument panel cluster ever comes on
and stays on, it means that something
may be wrong with the airbag system. If
this ever happens, have the vehicle
serviced promptly, because an adult-size
person sitting in the right front
passenger’s seat may not have the
protection of the frontal airbag. See
Airbag Readiness Light on page 247for
more on this, including important safety
information.
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Recommended Transfer Case Settings
Driving
ConditionsTransfer Case Settings
2
mAUTO
4WD4m4nN
Normal YES
Variable YES
Severe YES
Extreme YES
Vehicle in
Tow*YES
*SeeRecreational Vehicle Towing on page 424for
further information.
You can choose among ve driving settings:
Notice:Driving on clean, dry pavement in
Four-Wheel-Drive High or Four-Wheel-Drive
Low for an extended period of time may cause
premature wear on your vehicle’s powertrain.
Do not drive on clean, dry pavement in
Four-Wheel-Drive High or Four-Wheel-Drive
Low for extended periods of time.Indicator lights in the switches show the current
setting. The indicator lights will come on briey
when you turn on the ignition and the last chosen
setting 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.
Fast ashing means the conditions are not
being met to make the desired shift, typically the
vehicle is going too fast, the automatic
transmission is not in NEUTRAL, or the clutch
pedal is not fully pressed. Slow ashing means the
shift is in progress. It will stay on when the shift
is completed. If for some reason the transfer case
cannot make a requested shift, it will return to
the last chosen setting.
AUTO 4WD (Automatic Four-Wheel Drive):This
setting is ideal for use when road surface
traction conditions are variable. When driving your
vehicle in AUTO 4WD, the front axle is engaged,
but the vehicle’s power is primarily sent to the rear
wheels. When the vehicle’s software determines
a need for more traction, the system will
transfer more power to the front wheels. Driving in
this mode results in slightly lower fuel economy
than Two-Wheel Drive High.
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Electronic Transfer Case
If your four-wheel-drive
vehicle has the
electronic transfer case,
the transfer case
switches are located to
the left of the
instrument panel cluster.
Recommended Transfer Case Settings
Driving ConditionsTransfer Case Settings
2m4m4nN
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*SeeRecreational Vehicle Towing on page 424or
Towing Your Vehicle on page 423for further
information.
Use these switches to shift into and out of
four-wheel drive. You can choose among
three driving settings:
Indicator lights in the switches show you which
setting you are in. The indicator lights will come on
briey when you turn on the ignition and the last
chosen setting will stay on. If the lights do not
come on, you should take your vehicle in to your
dealer for service. An indicator light will ash
while shifting. Fast ashing means the conditions
are not being met to make the desired shift,
typically the vehicle is going too fast, the automatic
transmission is not in neutral, or the clutch
pedal is not fully pressed. Slow ashing means
the shift is in progress. It will stay on when the shift
is completed. 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 for
driving in most street and highway situations.
The front axle is not engaged in two-wheel drive.
164

Auxiliary Roof Mounted Lamp
If your vehicle has this feature, this button includes
wiring provisions for a dealer or a qualied
service center to install an auxiliary roof lamp.
This button is located
on the center of the
instrument panel near
the climate controls.
When the wiring is connected to an auxiliary roof
mounted lamp, pressing the button will activate
the lamp and illuminate an indicator light near the
button. Pressing the button again will turn off
the roof mounted lamp.
If your vehicle has this button, your vehicle may
have the snow plow prep package. For further
information seeAdding a Snow Plow or Similar
Equipment on page 416.
Instrument Panel Brightness
D(Instrument Panel Brightness):This feature
controls the brightness of the instrument panel
lights.
The thumbwheel for this feature is located next to
the headlamp control.
Move the thumbwheel up to adjust the instrument
panel lights and to return the radio display to
full brightness when the headlamps or parking
lamps are on. To turn on the dome lamps, move
the thumbwheel to the farthest position.
Dome Lamps
The dome lamps come on when a door is opened.
The dome lamps can be turned on by moving
the thumbwheel, located next to the exterior lamps
control, to the farthest position. In this position,
the dome lamps will remain on whether a door is
opened or closed.
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If the word OFF or the off symbol is lit on the
passenger airbag status indicator, it means that
the passenger sensing system has turned off
the right front passenger’s airbag. SeePassenger
Sensing System on page 103orAirbag Off
Switch on page 100for more on this, including
important safety information.
{CAUTION:
If the right front passenger’s airbag is
turned off for a person who is not in a risk
group identied by the national
government, that person will not have the
extra protection of an airbag. In a crash,
the airbag will not be able to inate and
help protect the person sitting there.
Do not turn off the passenger’s airbag
unless the person sitting there is in a risk
group. SeeAirbag Off Switch on page 100
for more on this, including important
safety information.If, after several seconds, all status indicator lights
remain on, or if there are no lights at all, there
may be a problem with the lights or the passenger
sensing system. See your dealer for service.
{CAUTION:
If the airbag off indicator and the airbag
readiness light ever come on together, it
means that something may be wrong with
the airbag system. If this ever happens,
have the vehicle serviced promptly,
because an adult-size person sitting in the
right front passenger seat may not have
the protection of the airbag. SeeAirbag
Readiness Light on page 247.
252

The ABS warning light should come on briey
when you turn the ignition key to RUN. If the light
does not come on then, have it xed so it will
be ready to warn you if there is a problem.
Traction Off Light
If your vehicle has 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 505.
United StatesCanada
256

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

PASSENGER DOOR AJAR
If the passenger’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 obstructions, 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.
RANGE SHIFT INHIBITED
(Allison Transmission®Only)
If the transmission is unable to shift into a selected
gear, this message will appear on the DIC. The
electronic shift position indicator on the instrument
panel cluster may blink when this occurs. To
make the vehicle shift to the requested gear, you
may have to shift back to PARK (P) or
NEUTRAL (N) and re-select the desired gear.
REDUCED ENGINE POWER
This message is displayed when the cooling
system temperature gets too hot and the engine
further enters the engine coolant protection mode.
SeeEngine Overheating on page 505for further
information.
This message will also display when the vehicle’s
engine power is reduced. Reduced engine
power can affect the vehicle’s ability to accelerate.
If this message is on, but there is no reduction
in performance, proceed to your destination. The
performance may be reduced the next time
the vehicle is driven. The vehicle may be driven at
a reduced speed while this message is on, but
acceleration and speed may be reduced. Anytime
this message stays on, the vehicle should be
taken to your dealer for service as soon as
possible.
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