2003 GMC YUKON tow

Mode 4:No automatic door unlock.
The following instructions tell you how to change the
automatic door unlock mode. Choose one of the
four programming options listed above before entering
the program mode. To enter the program mode, do
the following:
1. Begin with the ignition off. Then pull the turn
signal/multifunction lever toward you and hold
it there while you perform the next step.
2. Turn the key to RUN and LOCK twice. Then, with
the key in LOCK, release the turn
signal/multifunction lever. Once you do this, the
doors will lock and unlock, the horn will chirp twice,
and a 30-second timer will begin. You are now
ready to program the automatic door unlock feature.
3. Press the door unlock switch once. You will hear
one, two, three, or four chimes. The number of
chimes tells you which unlock mode is currently
selected. Continue to press the door unlock switch
until the number of chimes that you hear matches the
number of the mode that you want. If you take longer
than 30 seconds, the locks will automatically lock and
unlock and the horn will chirp twice to indicate that
you have left the program mode. If this occurs, you
can repeat the procedure beginning with Step 1 to
re-enter the programming mode.
You can exit the program mode any time by turning the
ignition to RUN (the doors will automatically lock and
unlock and the horn will chirp twice to indicate that youare leaving the program mode). If the lock/unlock
switches are not pressed while in the programming
mode, the current automatic settings will not be
modied.
See your dealer for more information.
Rear Door Security Locks
If your vehicle is equipped with this feature, you can
lock the rear side doors so they cannot be opened from
the inside by passengers.
This feature is located on
the inside edge of the rear
doors.
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Passlock®
Your vehicle is equipped with the
Passlock®theft-deterrent system.
Passlock
®is a passive theft-deterrent system.
Passlock®enables fuel if the ignition lock cylinder is
turned with a valid key. If a correct key is not used or the
ignition lock cylinder is tampered with, fuel is disabled.
If the engine stalls and the security lightashes,
wait until the light stopsashing before trying to restart
the engine. Remember to release the key from
START as soon as the engine starts.
If the engine is running and the security light comes on,
you will be able to restart the engine if you turn the
engine off. However, your Passlock
®system is
not working properly and must be serviced by your
dealer. Your vehicle is not protected by Passlock
®at this
time. You may also want to check the fuse (see
Fuses and Circuit Breakers on page 5-98.) See your
dealer for service.
In an emergency, call the GM Roadside Assistance
Center. SeeRoadside Assistance Program on page 7-5
under Customer Assistance Information.
Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle doesn’t need an elaborate
“break-in.”But it will perform better in the long run
if you follow these guidelines:
Keep your speed at 55 mph (88 km/h) or less for
the first 500 miles (805 km).
•Don’t drive at any one speed — fast or
slow — for the first 500 miles (805 km). Don’t
make full-throttle starts.
•Avoid making hard stops for the first 200 miles
(322 km) or so. During this time your new
brake linings aren’t yet broken in. Hard stops
with new linings can mean premature wear and
earlier replacement. Follow this breaking-in
guideline every time you get new brake linings.
•Don’t tow a trailer during break-in. See “Towing
a Trailer” in the Index for more information.
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{CAUTION:
It is dangerous to get out of your vehicle if the
shift lever is not fully in PARK (P) with the
parking brakefirmly set. Your vehicle can roll.
Don’t leave your vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move
suddenly. You or others could be injured. To
be sure your vehicle won’t move, even when
you’re on fairly level ground, always set your
parking brake and move the shift lever to
PARK (P). See“Shifting Into Park (P)”in the
Index. If you’re pulling a trailer, see“Towing a
Trailer”in the Index.
{CAUTION:
If you have four–wheel drive, your vehicle will
be free to roll–even if your shift lever is in
PARK (P)–if your transfer case is in NEUTRAL.
So, be sure the transfer case is in a drive gear,
two-wheel high (2H) or four–wheel high (4H) or
four-wheel low (4L)–not in NEUTRAL. See
″Shifting into Park (P)″in the index.
REVERSE (R):Use this gear to back up.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage your transmission.
Shift to REVERSE (R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of snow,
ice or sand without damaging your transmission,
see If You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-52.
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NEUTRAL (N):In this position, your engine doesn’t
connect with the wheels. To restart when you’re already
moving, use NEUTRAL (N) only. Also, use
NEUTRAL (N) when your two-wheel drive vehicle is
being towed.
{CAUTION:
Shifting into a drive gear while your engine is
“racing”(running at high speed) is dangerous.
Unless your foot isfirmly on the brake pedal,
your vehicle could move very rapidly. You
could lose control and hit people or objects.
Don’t shift into a drive gear while your engine
is racing.
Notice:Damage to your transmission caused by
shifting out of PARK (P) or NEUTRAL (N) with
the engine racing isn’t covered by your warranty.
DRIVE (D):This position is for normal driving. If
you need more power for passing, and you’re:
Going less than about 35 mph (56 km/h), push your
accelerator pedal about halfway down.
Going about 35 mph (56 km/h) or more, push the
accelerator all the way down.You’ll shift down to the next gear and have more power.
DRIVE (D) can be used when towing a trailer, carrying
a heavy load, driving on steep hills or for off-road driving.
You may want to shift the transmission to THIRD (3)
or, if necessary, a lower gear selection if the
transmission shifts too often.
THIRD (3):This position is also used for normal driving,
however it offers more power and lower fuel economy
than DRIVE (D).
SECOND (2):This position gives you more power but
lower fuel economy. You can use SECOND (2) on
hills. It can help control your speed as you go down
steep mountain roads, but then you would also want to
use your brakes off and on.
If you manually select SECOND (2) in a light duty
automatic transmission, the transmission will drive in
second gear. You may use this feature for reducing the
speed of the rear wheels when you are trying to start
your vehicle from a stop on slippery road surfaces.
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FIRST (1):This position gives you even more power
(but lower fuel economy) than SECOND (2). You
can use it on very steep hills, or in deep snow or mud.
If the shift lever is put in FIRST (1) while the vehicle
is moving forward, the transmission won’t shift intorst
gear until the vehicle is going slowly enough.
Notice:If your wheels won’t turn, don’t try to drive.
This might happen if you were stuck in very deep
sand or mud or were up against a solid object. You
could damage your transmission. Also, if you
stop when going uphill, don’t hold your vehicle there
with only the accelerator pedal. This could overheat
and damage the transmission. Use your brakes
or shift into PARK (P) to hold your vehicle in
position on a hill.
On cold days, approximately 32°F(0°C) or colder, your
transmission is designed to shift differently until the
engine reaches normal operating temperature. This is
intended to improve heater performance.Tow/Haul Mode
Your vehicle may be equipped with a tow/haul mode. If
so, the selector button is located on the end of the
column shift lever. You can use this feature to assist
when towing or hauling a heavy load. SeeTowing
a Trailer on page 4-61for more information.
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When tow/haul mode is
selected the tow/haul
indicator light will
illuminate.
The tow/haul mode also interacts with the Autoride™
feature, if your vehicle is so equipped, to enhance
the ride when trailering or with a loaded vehicle. See
Autoride™on page 4-60.
Four-Wheel Drive
If your vehicle has four-wheel drive, you can send your
engine’s driving power to all four wheels for extra
traction. To get the most satisfaction out of four-wheel
drive, you must be familiar with its operation. Read
the part that follows before using four-wheel drive. See
the appropriate text for the transfer case in your
vehicle.
Notice:Driving in the 4-WHEEL HIGH (4HI) or
4-WHEEL LOW (4LO) positions for a long time on
dry or wet pavement could shorten the life of
your vehicle’s drivetrain.
Front Axle Locking Feature
The front axle locks and unlocks automatically when
you shift the transfer case. Some delay for the axle to
lock or unlock is normal.
Automatic Transfer Case
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. See″Parking Brake″in the
Index.
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g(4LO):This setting also engages your front axle
and delivers extra torque. You may never need
this setting. It sends maximum power to all four wheels.
You might choose 4LO if you are driving off-road in
deep sand, deep mud, deep snow and climbing
or descending steep hills.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. See″Parking Brake″in the
Index.
NEUTRAL:Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-55orTowing
Your Vehicle on page 4-54for more information.Indicator lights in the switches show which setting you
are in. The indicator lights will come on briey when you
turn on the ignition and one will stay on. If the lights
do not come on, you should take your vehicle to your
dealer for service. An indicator light willash while
shifting the transfer case. It will remain illuminated when
the shift is complete. If for some reason the transfer
case cannot make a requested shift, it will return to the
last chosen setting.
If the SERVICE 4WD message stays on, you should
take your vehicle to your dealer for service. See″Service
4WD message″underDriver Information Center (DIC)
on page 3-53.
Shifting into 4HI or AUTO 4WD
Press and release the 4 hi or AUTO 4WD switch. This
can be done at any speed (except when shifting
from 4LO), and the indicator light willash while shifting.
It will remain illuminated when the shift is completed.
Shifting into 2HI
Press and release the 2 hi switch. This can be done at
any speed (except when shifting from 4LO).
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Shifting into NEUTRAL
To shift the transfer case to NEUTRAL do the following:
1. Make sure the vehicle is parked so that it will
not roll.
2. Set the parking brake.
3. Start the vehicle or turn the ignition to RUN.
4. Connect the vehicle to the towing vehicle.
5. Put the transmission in NEUTRAL (N).
6. Shift the transfer case to 2HI.
7. Simultaneously press and hold the 2HI and 4LO
buttons for 10 seconds. The red NEUTRAL light
will come on when the transfer case shift to
NEUTRAL is complete.
8. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second.
9. Turn the ignition off.
10. Place the transmission shift lever in PARK (P).
11. Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (2HI, 4HI, AUTO 4WD OR 4 LO).
4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. You may start the engine and shift the transmission
to the desired position.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to
enter the shift protection mode. This will protect the
transfer case from possible damage and will
only allow the transfer case to respond to one shift
per 10 seconds. The transfer case may stay in
this mode for up to three minutes.
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