2006 GMC SIERRA 1500 transmission

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.
3-58

OIL PRESSURE LOW
Notice:If you drive your vehicle while the engine oil
pressure is low, severe engine damage may occur.
If a low oil pressure warning appears on the Driver
Information Center (DIC), stop the vehicle as soon as
possible. Do not drive the vehicle until the cause of
the low oil pressure is corrected. SeeEngine Oil
(Gasoline Engine) on page 5-20for more information.
If low oil pressure levels occur, this message will be
displayed on the DIC and a chime will sound. Stop the
vehicle as soon as safely possible and do not operate it
until the cause of the low oil pressure has been corrected.
Check your oil as soon as possible and have your vehicle
serviced by your GM dealer. SeeEngine Oil (Gasoline
Engine) on page 5-20.
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 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.
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 5-37for additional
information.
RIGHT REAR DOOR AJAR (Crew Cab)
If the passenger’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.
3-60

If the message is displayed immediately after starting
the vehicle or the message appears while driving,
your Supplemental Brake Assist system needs service.
See your GM dealer. SeeBrake System Warning
Light on page 3-41for additional information.
SERVICE BRAKE SYSTEM
If there is a problem with the brake system, this
message will be displayed on the DIC. If this message
appears, stop as soon as possible and turn off the
vehicle. Restart the vehicle and check for the message
on the DIC display. If the message is still displayed
or appears again when you begin driving, the brake
system needs service. See your GM dealer.
SERVICE CHARGING SYSTEM
On some vehicles, if there is a problem with the battery
charging system, this message will appear on the DIC.
Under certain conditions, the battery warning light may
also turn on in the instrument panel cluster. SeeBattery
Warning Light on page 3-40. The battery will not be
charging at an optimal rate and the vehicle will lose the
ability to enter the fuel economy mode. The vehicle is
safe to drive, however you should have the electrical
system checked by your GM dealer. 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.
TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly, this
message may appear along with the check engine light
on the instrument panel. SeeMalfunction Indicator Lamp
on page 3-46. Fully reinstall the fuel cap. SeeFilling the
Tank on page 5-10. 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 and message off.
TRACTION ACTIVE
When the traction control system had detected that any
of the vehicle’s wheels are slipping, the traction control
system will activate and this message will appear on the
DIC. For more information, seeTraction Assist
System (TAS) on page 4-8.
TRANS (Transmission)
HOT IDLE ENGINE
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.
3-62

Do not drive your vehicle with overheated
transmission uid or while the transmission
temperature warning is displayed.
If the transmission uid in the vehicle gets hot, this
message will appear on the DIC along with a continuous
chime. Driving with the transmission uid temperature
high can cause damage to the vehicle. Stop the vehicle
and let it idle to allow the transmission to cool. This
message will clear and the chime will stop when the uid
temperature reaches a safe level. SeeTransmission
Temperature Gage on page 3-44.
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 6-4for the transmission your vehicle is
equipped with for the proper transmission maintenance
intervals. Also seeTransmission Temperature Gage on
page 3-44for more information.
3-63

TRANS (Transmission) IN WARM UP
(Allison Transmission®Only)
When temperatures are very cold, the transmission
will prevent certain operations such as shifts to certain
ranges and engaging the torque converter clutch to
protect against damage. When active, the DIC will
display the message TRANS IN WARM UP.
TURN SIGNAL ON
If a turn signal is left on for 3/4 of a mile (1.2 km), this
message will appear on the display and you will hear a
chime. Move the turn signal/multifunction lever to the
off position. 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.
DIC Vehicle Customization
Your vehicle may have customization capabilities that
allow you to program some features to one setting based
on your preference. All of the customizable options listed
may not be available on your vehicle. Only the options
available will be displayed on your Driver Information
Center (DIC).The default settings for the customization features were
set when your vehicle left the factory, but may have been
changed from their default state since then.
To change feature preferences, make sure the
ignition is on and the vehicle is in PARK (P). Press
the customization button to scroll through the available
customizable options.
After pressing the customization button, VEHICLE
SETTINGS will momentarily display before going to a
customization option.
Lock Doors (Automatic Transmission only)
If you have an automatic transmission vehicle, press the
customization button until LOCK DOORS appears in the
display. To select your preference for automatic locking,
press the select button while LOCK DOORS is displayed
on the DIC. Pressing the select button will scroll through
the following choices:
LOCK DOORS: IN GEAR (default):The doors will lock
when the vehicle is shifted out of PARK (P).
LOCK DOORS: WITH SPEED:The doors will lock
when the vehicle speed is above 8 mph (13 km/h) for
three seconds.
Choose one of the available options and press the
customization button while it is displayed on the DIC
to select it and move on to the next feature. For
more information on automatic door locks, see
Programmable Automatic Door Locks on page 2-10.
3-64

Unlock Doors (Automatic
Transmission only)
If you have an automatic transmission vehicle, press the
customization button until UNLOCK DOORS appears
in the display. To select your preference for automatic
unlocking, press the select button while UNLOCK
DOORS is displayed on the DIC. Pressing the select
button will scroll through the following choices:
UNLOCK DOORS: IN PARK (default):All of the doors
will unlock when the vehicle is shifted into PARK (P).
UNLOCK DRIVER: IN PARK:The driver’s door will be
unlocked when the vehicle is shifted into PARK (P).
UNLOCK DOORS: KEY OUT:All of the doors
will unlock when the key is taken out of the ignition.
UNLOCK DOORS: MANUALLY:The doors will not be
unlocked automatically.
Choose one of the available options and press the
customization button while it is displayed on the DIC
to select it and move on to the next feature. For
more information on automatic door locks, see
Programmable Automatic Door Locks on page 2-10.
Door Lock Delay (Crew Cab only)
If your DIC does not have this feature, you still may be
able to program the delayed locking feature. SeeDelayed
Locking on page 2-10for more information.
When locking the doors with the power lock switch or
the keyless entry transmitter and a door is open, the
delayed locking feature will delay locking the doors until
ve seconds after the last door is closed.
Press the customization button until DOOR LOCK
DELAY appears in the display. To select your preference
for delayed locking, press the select button while DOOR
LOCK DELAY is displayed on the DIC. Pressing the
select button will scroll through the following choices:
DOOR LOCK DELAY: OFF (default):The doors will
lock immediately when pressing the power lock switch
or the lock button on the keyless entry transmitter.
DOOR LOCK DELAY: ON:The doors will not lock until
ve seconds after the last door is closed. You will hear
three chimes to signal that the delayed locking feature is
in use. You can temporarily override delayed locking by
pressing the lock button on the door or keyless entry
transmitter a second time.
Choose one of the available options and press the
customization button while it is displayed on the DIC
to select it and move on to the next feature.
This feature will not operate if the key is in the ignition.
3-65

Remember: Anti-lock does not change the time you need
to get your foot up to the brake pedal or always decrease
stopping distance. If you get too close to the vehicle in
front of you, you will not have time to apply your brakes
if that vehicle suddenly slows or stops. Always leave
enough room up ahead to stop, even though you have
anti-lock brakes.
Using Anti-Lock
Do not pump the brakes. Just hold the brake pedal down
rmly and let anti-lock work for you. You may feel the
brakes vibrate, or you may notice some noise, but this
is normal.
Braking in Emergencies
With anti-lock brakes, you can steer and brake at the
same time. In many emergencies, steering can help
you more than even the very best braking.
Traction Assist System (TAS)
Your vehicle may have a Traction Assist System (TAS)
that limits wheel spin. This is especially useful in slippery
road conditions. The system operates only if it senses
that one or both of the rear wheels are spinning or
beginning to lose traction. When this happens, the
system reduces engine power to limit wheel spin.
The traction control system is enabled every time your
vehicle is started. The system will activate if it senses
that any of the wheels are spinning or beginning to lose
traction.
You may hear or feel the system working or notice
a lack of accelerator response, but this is normal.
The Traction Assist System may operate on dry roads
under some conditions. When this happens, you may
notice a reduction in acceleration. This is normal
and doesn’t mean there’s a problem with your vehicle.
Examples of these conditions include a hard acceleration
in a turn, an abrupt upshift or downshift of the
transmission or driving on rough roads.
If your vehicle is in cruise control when the TAS begins
to limit wheel spin, the cruise control will automatically
disengage. When road conditions allow you to safely
use it again, you may re-engage the cruise control.
SeeCruise Control on page 3-10.
4-8

When the traction off light is
on, the TAS is off and will
not limit wheel spin. Adjust
your driving accordingly.
The traction off light will come on under the following
conditions:
The Traction Assist System is turned off, either
by pressing the TAS on/off button, located on
the instrument panel, or by turning off the automatic
engagement feature of the TAS.
The transmission is in FIRST (1); TAS will not
operate in this gear. This is normal.
The vehicle is driven on an extremely rough road.
When the vehicle leaves the rough surface, slows
down or stops, the light will go off and TAS will turn
on again. This is normal.
A Traction Assist System, Anti-Lock Brake System
or engine-related problem has been detected and
the vehicle needs service.
If the vehicle has been driven with the TAS system
on for long periods of time, or if the vehicle has
gone through many several high speed braking
maneuvers the system may be automatically
disabled. The system will automatically re-enable
after approximately two minutes of not using
the brakes.
SeeTraction Off Light on page 3-43.
4-9