2008 GMC SIERRA trailer

Reading Lamps
If your vehicle has reading lamps they are located on
the overhead console.
To turn on the reading lamps, press the button
located next to each lamp. To turn them off, press the
button again.
Your vehicle may also have reading lamps in other
locations. To turn the lamps on or off, press the button
located next to the lamp.
If your vehicle has a DVD Rear Seat Entertainment
(RSE) system, press the lamp lenses to turn the lamps
on or off.
The lamps are xed and cannot be adjusted.
Cargo Lamp
The cargo lamps come on by turning the instrument
panel brightness control knob to the farthest clockwise
position. This knob is located on the instrument
panel and also turns on the dome lamps.
The cargo lamp can be used if more light is needed in
the cargo area of the vehicle or in the top-box
storage units.
Electric Power Management
The vehicle has Electric Power Management (EPM) that
estimates the battery’s temperature and state of
charge. It then adjusts the voltage for best performance
and extended life of the battery.
When the battery’s state of charge is low, the voltage is
raised slightly to quickly put the charge back in. When
the state of charge is high, the voltage is lowered slightly
to prevent overcharging. If the vehicle has a voltmeter
gage or a voltage display on the Driver Information
Center (DIC), you may see the voltage move up
or down. This is normal. If there is a problem, an alert
will be displayed.
The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles. This is
because the generator (alternator) may not be
spinning fast enough at idle to produce all the power
that is needed for very high electrical loads.
A high electrical load occurs when several of the
following loads are on: headlamps, high beams, fog
lamps, rear window defogger, climate control fan at high
speed, heated seats, engine cooling fans, trailer
loads, and loads plugged into accessory power outlets.
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If the Light is Flashing
The following can prevent more serious damage to your
vehicle:
Reduce vehicle speed.
Avoid hard accelerations.
Avoid 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 the vehicle.
Turn the ignition 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/retailer
for service as soon as possible.
If the Light Is On Steady
You might 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 5-10. The
diagnostic system can determine if the fuel cap hasbeen left off or improperly installed. A loose or missing
fuel cap allows 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 vehicle’s electrical system might be wet. The
condition is usually corrected when the electrical system
dries out. A few driving trips should turn the light off.
Have you recently changed brands of fuel?
If so, be sure to fuel your vehicle with quality fuel. See
Gasoline Octane on page 5-6. Poor fuel quality causes
the engine not to run as efficiently as designed. You
might notice this as stalling after start-up, stalling when
you put the vehicle into gear, misring, hesitation on
acceleration, or stumbling on acceleration — these
conditions might go away once the engine is warmed up.
This will be detected by the system and cause the light to
turn on.
If you experience one or more of these conditions,
change the fuel brand you use. It will require at least
one full tank of the proper fuel to turn the light off.
If none of the above steps have made the light turn off,
your dealer/retailer can check the vehicle. Your
dealer/retailer has the proper test equipment and
diagnostic tools to x any mechanical or electrical
problems that might have developed.
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DIC Operation and Displays (With
DIC Buttons)
If your vehicle has DIC buttons, the information below
explains the operation of this system.
The DIC has different displays which can be accessed
by pressing the DIC buttons located on the instrument
panel, next to the steering wheel.
The DIC displays trip, fuel, and vehicle system
information, and warning messages if a system problem
is detected.
The DIC also allows some features to be customized.
SeeDIC Vehicle Customization (With DIC Buttons)
on page 3-72for more information.
If your vehicle has DIC buttons, you can also use the
trip odometer reset stem to view some of the DIC
displays. See “DIC Operation and Displays (Without DIC
Buttons)” later in this section.
DIC Buttons
The buttons are the
trip/fuel, vehicle
information, customization,
and set/reset buttons.
The button functions are
detailed in the following
pages.
3(Trip/Fuel):Press this button to display the
odometer, trip odometer, fuel range, average economy,
fuel used, timer, and transmission temperature.
Some vehicles also display instantaneous economy and
an Active Fuel Management™ indicator.
T(Vehicle Information):Press this button to display
the oil life, units, tire pressure readings for vehicles
with the Tire Pressure Monitor System (TPMS), trailer
brake gain and output information for vehicles with
the Integrated Trailer Brake Control (ITBC) system,
engine hours, and Remote Keyless Entry (RKE)
transmitter programming.
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Also, be careful not to reset the OIL LIFE display
accidentally at any time other than when the oil has just
been changed. It cannot be reset accurately until the
next oil change. To reset the engine oil life system, see
Engine Oil Life System on page 5-18.
Units
Press the vehicle information button until UNITS
displays. This display allows you to select between
English or Metric units of measurement. Once in this
display, press the set/reset button to select between
ENGLISH or METRIC units. All of the vehicle information
will then be displayed in the unit of measurement
selected.
Tire Pressure
If your vehicle has the Tire Pressure Monitor System
(TPMS), the pressure for each tire can be viewed in the
DIC. The tire pressure will be shown in either pounds
per square inch (psi) or kilopascals (kPa). Press
the vehicle information button until the DIC displays
FRONT TIRES PSI (kPa) LEFT ## RIGHT ##. Press the
vehicle information button again until the DIC displays
REAR TIRES PSI (kPa) LEFT ## RIGHT ##.
If a low or high tire pressure condition is detected by the
system while driving, a message advising you to
check the pressure in a specic tire will appear in thedisplay. SeeInflation - Tire Pressure on page 5-74and
DIC Warnings and Messages on page 3-63for more
information.
If the tire pressure display shows dashes instead of a
value, there may be a problem with your vehicle. If this
consistently occurs, see your dealer/retailer for service.
Trailer Gain and Output
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, the trailer brake display appears in the
DIC. Press the vehicle information button until
TRAILER GAIN and OUTPUT display.
TRAILER GAIN shows the trailer gain setting. This
setting can be adjusted from 0.0 to 10.0 with either a
trailer connected or disconnected. To adjust this setting,
see “Integrated Trailer Brake Control System” under
Towing a Trailer on page 4-55for more information.
OUTPUT shows the power output to the trailer anytime
a trailer with electric brakes is connected. Output is
displayed in 0 to 10 bars. Dashes may appear in
the OUTPUT display. See “Integrated Trailer Brake
Control System” underTowing a Trailer on page 4-55
for more information.
Engine Hours
Press the vehicle information button until ENGINE
HOURS displays. This display shows the total number
of hours the engine has run.
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Relearn Remote Key
This display allows you to match Remote Keyless Entry
(RKE) transmitters to your vehicle. To match an RKE
transmitter to your vehicle:
1. Press the vehicle information button until PRESS
V
TO RELEARN REMOTE KEY displays.
2. Press the set/reset button until REMOTE KEY
LEARNING ACTIVE is displayed.
3. Press and hold the lock and unlock buttons on the
rst transmitter at the same time for about
15 seconds.
On vehicles with memory recall seats, the rst
transmitter learned will match driver 1 and
the second will match driver 2.
A chime will sound indicating that the transmitter is
matched.
4. To match additional transmitters at this time, repeat
Step 3.
Each vehicle can have a maximum of eight
transmitters matched to it.
5. To exit the programming mode, you must cycle the
key to LOCK/OFF.
Blank Display
This display shows no information.
DIC Operation and Displays
(Without DIC Buttons)
If your vehicle does not have DIC buttons, the
information below explains the operation of this system.
The DIC has different displays which can be accessed
by pressing the trip odometer reset stem located on the
instrument panel cluster. Pressing the trip odometer
reset stem will also turn off, or acknowledge, DIC
messages.
The DIC displays trip and vehicle system information,
and warning messages if a system problem is detected.
If your vehicle does not have DIC buttons, you can
use the trip odometer reset stem to view the following
displays: odometer, engine hours, trip odometer,
transmission temperature, trailer brake gain and output
information for vehicles with the Integrated Trailer
Brake Control (ITBC) system, oil life, Tire Pressure
Monitor System (TPMS) programming for vehicles with
the TPMS, Remote Keyless Entry (RKE) transmitter
programming, and display language.
If your vehicle has DIC buttons, you can use the
trip odometer reset stem to view the following
displays: odometer, engine hours, trip odometer, and
display language.
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Trip Odometer Reset Stem Menu Items
Odometer
Press the trip odometer reset stem until ODOMETER
displays. This display shows the distance the vehicle
has been driven in either miles (mi) or kilometers (km).
Engine Hours
To display the ENGINE HOURS, place the ignition in
LOCK/OFF or ACC/ACCESSORY, then press and hold
the trip odometer reset stem for four seconds while
viewing the ODOMETER. This display shows the total
number of hours the engine has run.
Trip Odometer
Press the trip odometer reset stem until TRIP displays.
This display shows the current distance traveled in
either miles (mi) or kilometers (km) since the last reset
for the trip odometer.
The trip odometer can be reset to zero by pressing and
holding the trip odometer reset stem while the trip
odometer is displayed.
The trip odometer has a feature called the retro-active
reset. This can be used to set the trip odometer to
the number of miles (kilometers) driven since the ignition
was last turned on. This can be used if the trip
odometer is not reset at the beginning of the trip.To use the retro-active reset feature, press and hold the
trip odometer reset stem for at least four seconds.
The trip odometer will display the number of miles (mi)
or kilometers (km) driven since the ignition was last
turned on and the vehicle was moving. Once the vehicle
begins moving, the trip odometer will accumulate
mileage. For example, if the vehicle was driven 5 miles
(8 km) before it is started again, and then the
retro-active reset feature is activated, the display will
show 5 miles (8 km). As the vehicle begins moving, the
display will then increase to 5.1 miles (8.2 km),
5.2 miles (8.4 km), etc.
Transmission Temperature
Press the trip odometer reset stem until TRANS
TEMP displays. This display shows the temperature
of the automatic transmission uid in either degrees
Fahrenheit (°F) or degrees Celsius (°C).
Trailer Gain and Output
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, the trailer brake display appears in the
DIC. Press the trip odometer reset stem until TRAILER
GAIN and OUTPUT display.
TRAILER GAIN shows the trailer gain setting. This
setting can be adjusted from 0.0 to 10.0 with either a
trailer connected or disconnected. To adjust this setting,
see “Integrated Trailer Brake Control System” under
Towing a Trailer on page 4-55for more information.
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OUTPUT shows the power output to the trailer anytime
a trailer with electric brakes is connected. Output is
displayed in 0 to 10 bars. Dashes may appear in
the OUTPUT display. See “Integrated Trailer Brake
Control System” underTowing a Trailer on page 4-55
for more information.
Oil Life
To access this display, the vehicle must be in PARK (P).
Press the trip odometer reset stem until OIL LIFE
REMAINING displays. This display shows an estimate
of the oil’s remaining useful life. If you see 99% OIL LIFE
REMAINING on the display, that means 99% of the
current oil life remains. The engine oil life system
will alert you to change the oil on a schedule consistent
with your driving conditions.
When the remaining oil life is low, the CHANGE
ENGINE OIL SOON message will appear on the display.
See “CHANGE ENGINE OIL SOON” underDIC
Warnings and Messages on page 3-63. You should
change the oil as soon as you can. SeeEngine
Oil (Gasoline Engine) on page 5-15. In addition to the
engine oil life system monitoring the oil life, additional
maintenance is recommended in the Maintenance
Schedule in this manual. SeeScheduled Maintenance
(Gasoline Engine) on page 6-4for more information.
Remember, you must reset the OIL LIFE display
yourself after each oil change. It will not reset itself.Also, be careful not to reset the OIL LIFE display
accidentally at any time other than when the oil has just
been changed. It cannot be reset accurately until the
next oil change. To reset the engine oil life system, see
Engine Oil Life System on page 5-18.
Relearn Tire Positions
Your vehicle may have this display. To access this
display, the vehicle must be in PARK (P). If your vehicle
has the Tire Pressure Monitor System (TPMS), after
rotating the tires or after replacing a tire or sensor, the
system must re-learn the tire positions. To re-learn
the tire positions, seeTire Pressure Monitor System on
page 5-76. SeeTire Inspection and Rotation on
page 5-81andDIC Warnings and Messages on
page 3-63for more information.
Relearn Remote Key
To access this display, the vehicle must be in PARK (P).
This display allows you to match Remote Keyless
Entry (RKE) transmitters to your vehicle. To match an
RKE transmitter to your vehicle:
1. Press the trip odometer reset stem until RELEARN
REMOTE KEY displays.
2. Press and hold the trip odometer reset stem for
three seconds.
The message REMOTE KEY LEARNING ACTIVE
will display.
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The following are the possible messages that can be
displayed and some information about them.
If your vehicle has the DURAMAX
®Diesel engine, see
the DURAMAX®Diesel manual for more information.
CHANGE ENGINE OIL SOON
This message displays when the engine oil needs to be
changed. When you change the engine oil, be sure
to reset the CHANGE ENGINE OIL SOON message.
SeeEngine Oil Life System on page 5-18for information
on how to reset the message. SeeEngine Oil (Gasoline
Engine) on page 5-15andScheduled Maintenance
(Gasoline Engine) on page 6-4for more information.
CHECK TIRE PRESSURE
If your vehicle has the Tire Pressure Monitor System
(TPMS), this message displays when the pressure
in one or more of the vehicle’s tires needs to be
checked. This message also displays LEFT FRONT,
RIGHT FRONT, LEFT REAR, or RIGHT REAR to
indicate which tire needs to be checked. You can
receive more than one tire pressure message at a time.
To read the other messages that may have been
sent at the same time, press the set/reset button or the
trip odometer reset stem. If a tire pressure message
appears on the DIC, stop as soon as you can. Have the
tire pressures checked and set to those shown on the
Tire Loading Information label. SeeTires on page 5-66,Loading Your Vehicle on page 4-36, andInflation - Tire
Pressure on page 5-74. The DIC also shows the tire
pressure values. See “DIC Operation and Displays (With
DIC Buttons)” earlier in this section. If the tire pressure
is low, the low tire pressure warning light comes on.
SeeTire Pressure Light on page 3-47.
CHECK TRAILER WIRING
On vehicles with the Integrated Trailer Brake Control
(ITBC) system, this message may display and a chime
may sound when one of the following conditions exists:
A trailer with electric brakes becomes disconnected
from the vehicle.
If the disconnect occurs while the vehicle is
stopped, this message clears itself after a
short time.
If the disconnect occurs while the vehicle is
moving, this message stays on until the ignition
is turned off.
There is a short in the wiring to the electric trailer
brakes.
When this message displays, power is no longer
available to the trailer brakes.
As soon as it is safe to do so, carefully pull your vehicle
over to the side of the road and turn the ignition off.
Check the wiring connection to the trailer and turn the
ignition back on. This message clears if the trailer
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