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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 5-38for 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, if equipped,
will acknowledge the message and clear it from the
DIC display. If your vehicle is not equipped with the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
SERVICE 4WD (Four-Wheel-Drive)
If a problem occurs with the four-wheel-drive system,
this message will appear 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
four-wheel-drive system needs service. See your
GM dealer.
SERVICE 4 WHEEL STEER
If a problem occurs with the four-wheel steer system,
this message will appear 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 four-wheel
steer system needs service. See your GM dealer. See
QUADRASTEER™ on page 4-14for more information.
Pressing any of the four DIC buttons, if equipped,
will acknowledge the message and clear it from the
DIC display. If your vehicle is not equipped with the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
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SERVICE AIR BAG
If there is a problem with the airbag system, this
message will be displayed on the DIC. Have your
GM dealer inspect the system for problems. SeeAirbag
Readiness Light on page 3-34andAirbag System on
page 1-63for more information. Pressing any of the
four DIC buttons, if equipped, will acknowledge
the message and clear it from the DIC display. If your
vehicle is not equipped with the four DIC buttons,
pressing the trip odometer reset stem will acknowledge
the message and clear it from the DIC display.
SERVICE BRAKE BOOSTER
If your vehicle has vacuum assist power brakes, this
message will be displayed on the DIC when there is a
problem with the Supplemental Brake Assist system.
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 3-40for additional information.
{CAUTION:
Your brake system may not be working
properly if the SERVICE BRAKE BOOSTER
message is displayed.
If the brake system warning light is also on,
you should have the vehicle towed for service.
SeeBrake System Warning Light on page 3-40.
If the brake system warning light is not on,
you still have brakes, but the supplemental
brake assist system on vehicles with rear disc
brakes may not operate properly. In the event
of a vacuum loss, you may not have vacuum
power assist for braking. The brake pedal
will be harder to push and it will take longer
to stop. If you continue to drive with this
message displayed it can lead to a crash.
Have the brake system serviced as soon as
possible.
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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 3-38. 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, if equipped,
will acknowledge the message and clear it from the
DIC display. If your vehicle is not equipped with the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
SERVICE RIDE CONTROL
If a problem occurs with the suspension system, this
message will appear on the DIC. If this message
appears, stop and turn off the vehicle. Restart the
vehicle and check for the message on the DIC display.
If this message is still displayed or appears again
when you begin driving, the air suspension system
needs service. See your GM dealer.
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 cluster. SeeMalfunction
Indicator Lamp on page 3-44. Reinstall the fuel cap
fully. 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 this 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. SeeTraction Assist System (TAS) on
page 4-8for more information.
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