2010 GMC SIERRA light

The theft-deterrent system will not activate if the doors
are locked with the vehicle's key or the manual door
lock. It activates only if you use the power door lock
switch with the door open or the RKE transmitter.
You should also remember that you can start your
vehicle with the correct ignition key if the alarm has
been set off.
To avoid setting off the alarm by accident:
.If you do not want to activate the theft-deterrent
system, the vehicle should be locked with the door
key after the doors are closed.
.Always unlock a door with the RKE transmitter.
Unlocking a door any other way will set off the
alarm if the system has been armed.
If you set off the alarm by accident, press unlock on the
RKE transmitter or place the key in the ignition and turn
it to START to turn it off.
Testing the Alarm
To test the alarm: 1. From inside the vehicle, lower the driver's window and open the driver's door.
2. Activate the system by locking the doors with the RKE transmitter.
3. Get out of the vehicle, close the door and wait for the security light to go out.
4. Then reach in through the window, unlock the door with the manual door lock and open the door.
This should set off the alarm.
If the alarm does not sound when it should but the
headlamps flash, check to see if the horn works.
The horn fuse may be blown. To replace the fuse,
see Fuses and Circuit Breakers on page 6‑118.
If the alarm does not sound or the headlamps do not
flash, see your dealer/retailer for service.
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PASS-Key®III+ Electronic
Immobilizer
See Radio Frequency Statementon page 8‑19for information regarding Part 15 of the Federal
Communications Commission (FCC) Rules and
RSS-210/211 of Industry and Science Canada.
PASS-Key®III+ Electronic
Immobilizer Operation
Your vehicle has PASS-Key®III+ (Personalized
Automotive Security System) theft-deterrent system.
PASS-Key
®III+ is a passive theft-deterrent system.
The system is automatically armed when the key is
removed from the ignition.
The system is automatically disarmed when the key is
turned to ON/RUN, ACC/ACCESSORY or START from
the LOCK/OFF position. You do not have to manually arm or disarm the system.
The security light will come on if there is a problem with
arming or disarming the theft-deterrent system.
When the PASS-Key
®III+ system senses that someone
is using the wrong key, it prevents the vehicle from
starting. Anyone using a trial-and-error method to start
the vehicle will be discouraged because of the high
number of electrical key codes.
If the engine does not start and the security light on
the instrument panel cluster comes on when trying to
start the vehicle, there may be a problem with your
theft-deterrent system. Turn the ignition off and
try again.
If the engine still does not start, and the key appears to
be undamaged, try another ignition key. At this time,
you may also want to check the fuse, see Fuses and
Circuit Breakers
on page 6‑118. If the engine still
does not start with the other key, your vehicle needs
service. If your vehicle does start, the first key may be
faulty. See your dealer/retailer who can service the
PASS-Key
®III+ to have a new key made. In an
emergency, contact Roadside Assistance.
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It is possible for the PASS-Key®III+ decoder to learn
the transponder value of a new or replacement key.
Up to 10 keys may be programmed for the vehicle.
The following procedure is for programming additional
keys only. If all the currently programmed keys are lost
or do not operate, you must see your dealer/retailer or a
locksmith who can service PASS-Key
®III+ to have keys
made and programmed to the system.
See your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to get a new key blank that is cut
exactly as the ignition key that operates the system.
To program the new additional key:
1. Verify that the new key has a
1stamped on it.
2. Insert the original, already programmed, key in the ignition and start the engine. If the engine will not
start, see your dealer/retailer for service. 3. After the engine has started, turn the key to
LOCK/OFF, and remove the key.
4. Insert the new key to be programmed and turn it to the ON/RUN position within five seconds of turning
the ignition to the LOCK/OFF position in Step 3.
The security light will turn off once the key has
been programmed.
5. Repeat Steps 1 through 4 if additional keys are to be programmed.
If you lose or damage your PASS-Key
®III+ key, see
your dealer/retailer or a locksmith who can service
PASS-Key
®III+ to have a new key made.
Do not leave the key or device that disarms or
deactivates the theft deterrent system in the vehicle.
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Ignition Positions
The ignition switch has
four different positions.
To shift out of P (Park), the ignition must be in ON/RUN
or ACC/ACCESSORY and the regular brake pedal must
be applied.
A (LOCK/OFF) : This position locks the ignition. It also
locks the transmission on automatic transmission
vehicles. The key can be removed in LOCK/OFF.
On vehicles with an automatic transmission, the shift
lever must be in P (Park) to turn the ignition switch to
LOCK/OFF. The steering can bind with the wheels turned off center.
If this happens, move the steering wheel from right to
left while turning the key to ACC/ACCESSORY. If this
doesn't work, then the vehicle needs service.
Notice:
Using a tool to force the key to turn in the
ignition could cause damage to the switch or break
the key. Use the correct key, make sure it is all the
way in, and turn it only with your hand. If the key
cannot be turned by hand, see your dealer/retailer.
B (ACC/ACCESSORY) : This position lets things like
the radio and the windshield wipers operate while the
engine is off. Use this position if the vehicle must be
pushed or towed.
C (ON/RUN) : This position can be used to operate the
electrical accessories and to display some instrument
panel cluster warning and indicator lights. The switch
stays in this position when the engine is running.
The transmission is also unlocked in this position on
automatic transmission vehicles.
If you leave the key in the ACC/ACCESSORY or
ON/RUN position with the engine off, the battery could
be drained. You may not be able to start the vehicle if
the battery is allowed to drain for an extended period
of time.
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Automatic Transmission Operation
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
Vehicles with an automatic transmission have an
electronic shift position indicator within the instrument
panel cluster. This display comes on when the ignition
key is turned to the ON/RUN position.
There are several different positions for the shift lever.
Hydra-Matic®4-Speed
Automatic Transmission
Heavy Duty 6-Speed Automatic Transmission Shown (Light Duty 6 Speed Similar)
See “Range Selection Mode” later in this section.
P (Park) : This position locks the rear wheels. It is the
best position to use when starting the engine because
the vehicle cannot move easily. When parked on a hill,
especially when the vehicle has a heavy load, you
might notice an increase in the effort to shift out of
P (Park). See Torque Lock (Automatic Transmission)
under Shifting Into Park
on page 3‑51for more
information.
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Tow/Haul Mode
Vehicles with an automatic transmission have a tow/
haul mode. The tow/haul mode adjusts the transmission
shift pattern to reduce shift cycling, providing increased
performance, vehicle control, and transmission cooling
when towing or hauling heavy loads.
The selector button is located on the end of the shift
lever. Turn the tow/haul on and off by pressing the
button. When the tow/haul is on, a light on the
instrument panel cluster will come on.
SeeTow/Haul Mode Light
on page 4‑49for more
information. Also see Tow Haul Mode under
Towing a Trailer
on
page 5‑50for more information.
Tow/Haul Mode (Allison Transmission®
or Hydra-Matic®6-Speed Automatic
Transmission)
Vehicles with an Allison or Hydra-Matic®6-speed
automatic transmission®have a tow/haul mode. The
tow/haul mode adjusts the transmission shift pattern to
reduce shift cycling, providing increased performance,
vehicle control, and transmission cooling when towing
or hauling heavy loads.
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Turn the tow/haul mode on and off by pressing the
button, located on the end of the shift lever. When the
tow/haul is on, a light on the instrument panel cluster
will come on.
SeeTow/Haul Mode Light
on page 4‑49for more
information.
Also see “Tow Haul Mode” underTowing a Trailer
on
page 5‑50for more information.
Grade Braking (Allison Transmission®
or Hydra-Matic®6-Speed Automatic
Transmission)
The Grade Braking shift modes can be activated by
pressing the button on the end of the shift control lever.
While in Range Selection Mode , Grade Braking is
deactivated allowing the driver to select a desired range
of gears.
Grade Braking is only active while the Tow/Haul Mode
is selected and you are not in the Range Selection
Mode. See “Tow/Haul Mode listed previously and
Automatic Transmission Operation
on page 3‑28for
more information on the Range Selection Mode. Grade
Braking assists in maintaining desired vehicle speeds
when driving on downhill grades by automatically
implementing a shift schedule that utilizes the engine
and transmission to slow the vehicle. This reduces wear
on the braking system and increases control of the vehicle. Grade Braking monitors vehicle speed,
acceleration, engine torque and brake pedal usage.
Using this information, it detects when the truck is on a
downhill grade and the driver desires to slow the vehicle
by pressing the brake.
Also see
Towing a Trailer
on page 5‑50for more
information.
Cruise Grade Braking (Allison
Transmission®or Hydra-Matic®
6-Speed Automatic Transmission)
Cruise Grade Braking assists when driving on a
downhill grade. It maintains vehicle speed by
automatically implementing a shift schedule that uses
the engine and the transmission to slow the vehicle.
Cruise Grade Braking operates while Cruise Control is
engaged in Tow/Haul mode to assist in maintaining
vehicle speed under loaded vehicle conditions.
It utilizes vehicle acceleration and deviation from
desired speed to determine the correct gear for the
operating condition. If vehicle speed is above the
desired speed the transmission will downshift to slow
the vehicle. If vehicle speed is near or below desired
speed the trans will upshift, allowing vehicle speed to
increase.
While in the Range Select Mode (RSM) mode, cruise
grade braking is not available.
See Automatic Transmission Operation on page 3‑28.
3-35

A Four-Wheel Drive
indicator light comes on
when you shift into
four-wheel drive and
the front axle engages.
SeeFour-Wheel-Drive
Light on page 4‑49.
Some delay between shifting and when the indicator
light comes on is normal.
Recommended Transfer Case Settings
Driving Conditions Transfer Case Settings
2m 4m4n N
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*See Recreational Vehicle Towing
on page 5‑43or
Towing Your Vehicle on page 5‑43
Notice: Driving on clean, dry pavement in
four-wheel drive for an extended period of time can
cause premature wear on the vehicle's powertrain.
Do not drive on clean, dry pavement in Four-Wheel
Drive for extended periods of time.
4
n(Four-Wheel-Drive Low): This setting also engages
the front axle and delivers extra torque. You may never
need Four-Wheel-Drive Low. It sends maximum power
to all four wheels. You might choose Four-Wheel-Drive
Low if you are driving off-road in deep sand, deep
mud, deep snow, and while climbing or descending
steep hills.
If the vehicle has StabiliTrak
®, shifting into
Four-Wheel-Drive Low will turn Traction Control and
StabiliTrak
®off. See StabiliTrak®System on page 5‑6.
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