2005 GMC YUKON ac system

Notice:If the jumper cables are connected or
removed in the wrong order, electrical shorting may
occur and damage the vehicle. The repairs would
not be covered by your warranty. Always connect
and remove the jumper cables in the correct
order, making sure that the cables do not touch
each other or other metal.
A. Heavy, Unpainted Metal Engine Part or Remote
Negative (−) Terminal
B. Good Battery or Remote Positive (+) and Remote
Negative (−) Terminals
C. Dead Battery or Remote Positive (+) TerminalTo disconnect the jumper cables from both vehicles
do the following:
1. Disconnect the black negative (−) cable from the
vehicle that had the bad battery.
2. Disconnect the black negative (−) cable from the
vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the other
vehicle.
5. Return the positive (+) remote terminal cover,
if equipped, to its original position.
All-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. However, there are two additional systems that
need lubrication.
Transfer Case
When to Check Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant. SeeScheduled
Maintenance on page 6-4. Jumper Cable Removal
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To get an accurate reading, the vehicle should be on a
level surface.
The proper level for the 1500 Series is from
5/8 inch to 1 5/8 inch (15 mm to 40 mm) below the
bottom of the ller plug hole.
The proper level for the 2500 Series is from
0 to 1/2 inch (0 to 13 mm) below the bottom of the
ller plug hole.
The proper level for the 1500 and 2500 series
vehicles with QUADRASTEER™ (4-Wheel Steer) is
from 0 to 1/4 inch (0 to 6 mm) below the ller
plug hole.
Add only enough uid to reach the proper level.
What to Use
To determine what kind of lubricant to use, see
Recommended Fluids and Lubricants on page 6-13.
Four-Wheel Drive
Lubricant checks in this section also apply to these
vehicles. There are two additional systems that need
lubrication.
Transfer Case
When to Check Lubricant
It is not necessary to regularly check transfer case uid
unless you suspect there is a leak, or you hear an
unusual noise. A uid loss could indicate a problem.
Have it inspected and repaired.
How to Check Lubricant
To get an accurate reading, the vehicle should be on a
level surface.Automatic Transfer Case
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Tire Size
The following examples show the different parts
of a tire size.
(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter P as the
rst character in the tire size means a passenger
vehicle tire engineered to standards set by the U.S. Tire
and Rim Association.(A) Light Truck (LT-Metric) Tire:The United States
version of a metric tire sizing system. The letters LT as
the rst two characters in the tire size means a light
truck tire engineered to standards set by the U.S. Tire
and Rim Association.
(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example, if
the tire size aspect ratio is 75, as shown in item C of the
light truck (LT-Metric) tire illustration, it would mean
that the tire’s sidewall is 75% as high as it is wide.
(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The
letter R means radial ply construction; the letter
D means diagonal or bias ply construction; and the
letter B means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:The service description
indicates the load range and speed rating of a tire.
The load index can range from 1 to 279. Speed ratings
range from A to Z. Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
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Tread:The portion of a tire that comes into contact
with the road.
Treadwear Indicators:Narrow bands, sometimes
called “wear bars,” that show across the tread of a tire
when only 1/16 inch (1.6 mm) of tread remains. See
When It Is Time for New Tires on page 5-70.
UTQGS (Uniform Tire Quality Grading Standards):A
tire information system that provides consumers with
ratings for a tire’s traction, temperature, and treadwear.
Ratings are determined by tire manufacturers using
government testing procedures. The ratings are molded
into the sidewall of the tire. SeeUniform Tire Quality
Grading on page 5-72.
Vehicle Capacity Weight:The number of designated
seating positions multiplied by 150 lbs (68 kg) plus
the rated cargo load. SeeLoading Your Vehicle
on page 4-51.
Vehicle Maximum Load on the Tire:Load on an
individual tire due to curb weight, accessory weight,
occupant weight, and cargo weight.
Vehicle Placard:A label permanently attached to a
vehicle showing the vehicle’s capacity weight and
the original equipment tire size and recommended
ination pressure. See “Tire and Loading Information
Label” underLoading Your Vehicle on page 4-51.Ination - Tire Pressure
Tires need the correct amount of air pressure to operate
effectively.
Notice:Do not let anyone tell you that
under-ination or over-ination is all right. It is not.
If your tires do not have enough air (under-ination),
you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-ination), you
can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazards
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A Tire and Loading Information label is attached to the
vehicle’s center pillar (B-pillar), below the driver’s
door lock post (striker). This label lists your vehicle’s
original equipment tires and their recommended cold tire
ination pressures. The recommended cold tire
ination pressure, shown on the label, is the minimum
amount of air pressure needed to support your vehicle’s
maximum load carrying capacity.
For additional information regarding how much weight
your vehicle can carry, and an example of the tire
and loading information label, seeLoading Your Vehicle
on page 4-51.
When to Check
Check your tires once a month or more. Do not forget to
check the spare tire. For additional information
regarding the spare tire, seeSpare Tire on page 5-95.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You cannot tell if your tires are properly inated
simply by looking at them. Radial tires may look properly
inated even when they’re underinated. Check the tire’s
ination pressure when the tires are cold. Cold means
your vehicle has been sitting for at least three hours or
driven no more than 1 mile (1.6 km).Remove the valve cap from the tire valve stem. Press
the tire gage rmly onto the valve to get a pressure
measurement. If the cold tire ination pressure matches
the recommended pressure on the Tire and Loading
Information label, no further adjustment is necessary.
If the ination pressure is low, add air until you reach the
recommended amount.
If you overll the tire, release air by pushing on the
metal stem in the center of the tire valve. Recheck the
tire pressure with the tire gage.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
Tire Pressure Monitor System
The Tire Pressure Monitor (TPM) system uses radio
and sensor technology to check tire pressure levels.
If your vehicle has this feature, sensors are mounted on
each tire and wheel assembly, except the spare tire.
The TPM sensors transmit tire pressure readings
to a receiver located in the vehicle.
When a low tire pressure condition is detected, the TPM
system will display the CHECK TIRE PRESSURE
warning message on the Driver Information Center (DIC);
and at the same time illuminate the low tire pressure
warning symbol. For additional information and details
about the DIC operation and displays seeDIC Operation
and Displays on page 3-55andDIC Warnings and
Messages on page 3-58.
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When the tire pressure
monitoring system warning
light is lit, one or more
of your tires is signicantly
under-inated.
You should stop and check your tires as soon as
possible, and inate them to the proper pressure as
indicated on the vehicle’s tire information placard.
Driving on a signicantly under-inated tire causes the
tire to overheat and can lead to tire failure.
Under-ination also reduces fuel efficiency and tire tread
life, and may affect the vehicle’s handling and stopping
ability. Each tire, including the spare, should be
checked monthly when cold and set to the
recommended ination pressure as specied in the
vehicle placard and owner’s manual.
The Tire and Loading Information label (tire information
placard) shows the size of your vehicle’s original tires and
the correct ination pressure for your vehicle’s tires when
they are cold. SeeInation - Tire Pressure on page 5-64.
For the location of the tire and loading information label,
seeLoading Your Vehicle on page 4-51.Your vehicle’s TPM system can alert you about a low
tire pressure condition but it does not replace normal tire
maintenance. SeeTire Inspection and Rotation on
page 5-68andTires on page 5-57.
Notice:Do not use a tire sealant if your vehicle is
equipped with Tire Pressure Monitors. The liquid
sealant can damage the tire pressure monitor
sensors.
TPM Sensor Identication Codes
Each TPM sensor has a unique identication code. Any
time you rotate your vehicle’s tires or replace one or
more of the TPM sensors, the identication codes
will need to be matched to the new tire/wheel position.
Each tire/wheel position is matched to a sensor, by
increasing or decreasing the tire’s air pressure.
The sensors are matched to the tire/wheel positions in
the following order: left front (LF), right front (RF),
right rear (RR) and left rear (LR).
You will have one minute to match the rst tire/wheel
position, and ve minutes overall to match all four
tire/wheel positions. If it takes longer than one minute,
to match the rst tire and wheel, or more than ve
minutes to match all four tire and wheel positions the
matching process stops and you will need to start over.
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The TPM sensor matching process is outlined below:
1. Set the Parking brake.
2. Turn the ignition switch to RUN with the engine off.
3. Turn the exterior lamp switch from “Off” to “On”
four times within 3 seconds. A double horn chirp
will sound and the TPM low tire warning light
will begin to ash. The double horn chirp and
ashing TPM warning light indicate that the TPM
matching process has started. The TPM warning
light should continue ashing throughout the
matching procedure. The SERVICE TIRE
MONITOR message will be displayed on the
Driver Information Center (DIC).
4. Start with the left (driver’s side) front tire.
5. Remove the valve cap from the valve cap stem.
Activate the TPM sensor by increasing or
decreasing the tire’s air pressure for 10 seconds,
then stop and listen for a single horn chirp.
The single horn chirp should sound within
15 seconds, conrming that the sensor identication
code has been matched to this tire and wheel
position. If you do not hear the conrming single
horn chirp, you will need to start over with step
number one. To let air-pressure out of a tire you can
use the pointy end of the valve cap, a pencil-style
air pressure gage or a key.6. Proceed to the right (passenger’s side) front tire,
and repeat the procedure in Step 5.
7. Proceed to the right (passenger’s side) rear tire,
and repeat the procedure in Step 5.
8. Proceed to the left (driver’s side) rear tire, and
repeat the procedure in Step 5.
9. After hearing the conrming horn chirp for the left
rear tire, check to see if the TPM warning light is
still ashing. If yes, turn the ignition switch to LOCK.
10. Set all four tires to the recommended air pressure
level as indicated on the Tire and Loading
Information label.
11. Put the valve caps back on the valve stems
The spare tire does not have a TPM sensor. If you
replace one of the road tires with the spare, the CHECK
TIRE PRESSURE message will be displayed on the
DIC screen. This message should go off once you
re-install the road tire containing the TPM sensor. The
SERVICE TIRE MONITOR message is displayed
when the TPM system is malfunctioning. One or more
missing or inoperable TPM sensors will cause the
service tire monitor message to be displayed. See your
dealer for service.
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Federal Communications Commission and
Industry and Science Canada
The TPM system operates on a radio frequency subject
to Federal Communications Commission (FCC) Rules
and with Industry and Science Canada.
This device complies with Part 15 of the FCC Rules and
with RSS-210 of Industry and Science Canada.
Operation is subject to the following two conditions:
(1) This device may not cause harmful interference, and
(2) this device must accept any interference received
including interference that may cause undesired
operation of the device.
Changes or modications to this system by other than
an authorized service facility could void authorization to
use this equipment.
Tire Inspection and Rotation
Tires should be rotated every 5,000 to 8,000 miles
(8 000 to 13 000 km).
Any time you notice unusual wear, rotate your tires as
soon as possible and check wheel alignment. Also
check for damaged tires or wheels. SeeWhen It Is Time
for New Tires on page 5-70andWheel Replacement
on page 5-73for more information.
Make sure the spare tire is stored securely. Push,
pull, and then try to rotate or turn the tire. If it moves,
use the ratchet/wheel wrench to tighten the cable.
SeeChanging a Flat Tire on page 5-76.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The rst rotation
is the most important. SeeScheduled Maintenance
on page 6-4.
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