ac system GMC YUKON 2005 Manual Online

Rear Passenger Console Control
To control the rear climate control from the rear
passenger seat position, use the rear passenger console
control. The driver overhead control fan knob must be
set to the AUX position.
The rear seat controls have the following settings:
O(On/Off):Press this button to turn the rear seat
comfort controls on or off when the front overhead
control is set to AUX.
%(Mode):Press this button to select the air delivery
mode and AUTO mode. Choose AUTO if you want
the system to automatically regulate the airow.
See “Auto Mode” later in this section for more
information on using this feature.
b(Temperature):Press this button up or down to
increase or decrease the temperature setting.
w9x(Fan):Press this button up or down to adjust
the fan speed. Choose AUTO if you want the system
to automatically choose the fan speed to maintain
a selected temperature. See “Auto Mode” following for
more information on using this feature.
AUTO Mode
When using the system in auto mode, nd your
comfort setting by placing the temperature control to
74°F (23°C) and allowing about 20 minutes for the
system to regulate. Then adjust the temperature setting
as necessary. If you choose full cold 60° F (15°C),
the system will remain at the maximum cooling setting.
If you choose full hot 90°F (32°C), the system will
remain at the maximum heat setting. Rear Controls
3-35

Warning Lights, Gages, and
Indicators
This part describes the warning lights and gages that may
be on your vehicle. The pictures will help you locate them.
Warning lights and gages can signal that something is
wrong before it becomes serious enough to cause
an expensive repair or replacement. Paying attention to
your warning lights and gages could also save you
or others from injury.
Warning lights come on when there may be or is a
problem with one of your vehicle’s functions. As you
will see in the details on the next few pages, some
warning lights come on briey when you start the engine
just to let you know they’re working. If you are familiar
with this section, you should not be alarmed when
this happens.Gages can indicate when there may be or is a problem
with one of your vehicle’s functions. Often gages
and warning lights work together to let you know when
there’s a problem with your vehicle.
When one of the warning lights comes on and stays on
when you are driving, or when one of the gages
shows there may be a problem, check the section that
tells you what to do about it. Please follow this
manual’s advice. Waiting to do repairs can be
costly – and even dangerous. So please get to know
your warning lights and gages. They’re a big help.
Your vehicle also has a driver information system that
works along with the warning lights and gages. See
Driver Information Center (DIC) on page 3-54.
3-36

Safety Belt Reminder Light
When the key is turned to RUN or START, a chime will
be provided for several seconds to remind people to
buckle their safety belts. The driver safety belt light will
also be provided and stay on for several seconds,
then it will ash for several more. You should buckle
your seat belt.
If your vehicle is not
equipped with the
passenger sensing system,
this chime and light will be
repeated if the driver
remains unbuckled and
the vehicle is in motion.
SeePassenger Sensing System on page 1-75for more
information.
If the driver’s belt is buckled, neither the chime nor the
light will come on.
Airbag Readiness Light
There is an airbag readiness light on the instrument
panel cluster, which shows the airbag symbol. The
system checks the airbag’s electrical system for
malfunctions. The light tells you if there is an electrical
problem. The system check includes the airbag
sensors, the airbag modules, the passenger sensing
system (if equipped), the wiring and the crash sensing
and diagnostic module. For more information on the
airbag system, seeAirbag System on page 1-66.
This light will come on
when you start your
vehicle, and it will ash
for a few seconds.
This means the system
is ready.
If the airbag readiness light stays on after you start
the vehicle or comes on when you are driving,
your airbag system may not work properly.
Have your vehicle serviced right away.
3-39

Passenger Airbag Status Indicator
If your vehicle has a passenger sensing system,
your rearview mirror will have a passenger airbag
status indicator.When the ignition key is turned to RUN or START, the
passenger airbag status indicator will light ON and
OFF, or the symbol for on and off, for several seconds
as a system check. Then, after several more seconds,
the status indicator will light either ON or OFF, or either
the on or off symbol to let you know the status of the
right front passenger’s frontal airbag.
If the word ON or the on symbol is lit on the passenger
airbag status indicator, it means that the right front
passenger’s frontal airbag is enabled (may inate).
{CAUTION:
If the on indicator comes on when you have a
rear-facing child restraint installed in the right
front passenger’s seat, it means that the
passenger sensing system has not turned off
the passenger’s frontal airbag. A child in a
rear-facing child restraint can be seriously
injured or killed if the right front passenger’s
airbag inates. This is because the back of the
rear-facing child restraint would be very close
to the inating airbag. Do not use a rear-facing
child restraint in the right front passenger’s
seat if the airbag is turned on. Passenger Airbag Status Indicator – United States
Passenger Airbag Status Indicator – Canada
3-40

Your vehicle has a rear seat that will accommodate a
rear-facing child restraint. A label on your sun visor says,
“Never put a rear-facing child seat in the front.” This
is because the risk to the rear-facing child is so great,
if the airbg deploys.
{CAUTION:
Even though the passenger sensing system is
designed to turn off the passenger’s frontal
airbag if the system detects a rear-facing child
restraint, no system is failsafe, and no one can
guarantee that an airbag will not deploy under
some unusual circumstance, even though it is
turned off. General Motors recommends that
rear-facing child restraints be secured in the
rear seat, even if the airbag is off.
If the word OFF or the off symbol is lit on the airbag
status indicator, it means that the passenger sensing
system has turned off the right front passenger’s frontal
airbag. SeePassenger Sensing System on page 1-75
for more on this, including important safety information.If, after several seconds, all status indicator lights
remain on, or if there are no lights at all, there may be
a problem with the lights or the passenger sensing
system. See your dealer for service.
{CAUTION:
If the off indicator and the airbag readiness
light ever come on together, it means that
something may be wrong with the airbag
system. If this ever happens, have the vehicle
serviced promptly, because an adult-size
person sitting in the right front passenger seat
may not have the protection of the frontal
airbag. SeeAirbag Readiness Light on
page 3-39.
3-41

Battery Warning Light
If this light is displayed
when the engine is
running, you may have
a problem with your
charging system.
The battery display will also stay on while the key is in
RUN until the engine is started.
If the light stays on after starting the engine it could
indicate a problem with the generator drive belt, or some
other charging system problem. Have it checked right
away. Driving with this light displayed could drain
your battery.
If you must drive a short distance with this light
displayed, it helps to turn off all your accessories,
such as the radio and the air conditioner.
Voltmeter Gage
When your engine is not
running, but the ignition
is in RUN, this gage shows
your battery’s state of
charge in DC volts.
When the engine is running, the gage shows the
condition of the charging system. The gage may
transition from a higher to lower or a lower to higher
reading, this is normal. Readings between the low and
high warning zones indicate the normal operating
range.
3-42

Readings in the low warning zone may occur when a
large number of electrical accessories are operating in
the vehicle and the engine is left at an idle for an
extended period. This condition is normal since the
charging system is not able to provide full power
at engine idle. As engine speeds are increased, this
condition should correct itself as higher engine speeds
allow the charging system to create maximum power.
You can only drive for a short time with the reading
in either warning zone. If you must drive, turn off
all unnecessary accessories.
Readings in either warning zone indicate a possible
problem in the electrical system. Have the vehicle
serviced as soon as possible.
Brake System Warning Light
With the ignition on, the brake system warning light
will ash when you set the parking brake. The light will
ash if the parking brake doesn’t release fully. If you
try to drive with the parking brake engaged, a chime
will sound when the vehicle speed is greater than
3 mph (5 km/h).Your vehicle’s hydraulic brake system is divided into
two parts. If one part isn’t working, the other part can
still work and stop you. For good braking, though,
you need both parts working well.
If the warning light comes on and a chime sounds there
could be a brake problem. Have your brake system
inspected right away.
This light should come on briey when you turn the
ignition key to RUN. If it doesn’t come on then, have
it xed so it will be ready to warn you if there’s a
problem.United States
Canada
3-43

If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push or may go closer to the oor. It may
take longer to stop. If the light is still on, have the vehicle
towed for service. SeeTowing Your Vehicle on
page 4-62.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you have pulled off the road and
stopped carefully, have the vehicle towed for
service.
Anti-Lock Brake System Warning
Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay on
for several seconds.
That’s normal. If the light doesn’t come on then, have
it xed so it will be ready to warn you if there is a
problem.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. You will also hear a
chime sound when the light is on steady. If the regular
brake system warning light isn’t on, you still have
brakes, but you don’t have anti-lock brakes. If the
regular brake system warning light is also on you don’t
have anti-lock brakes and there’s a problem with
your regular brakes. In addition to both lights, you will
also hear a chime sound on the rst occurrence of
a problem and each time the vehicle is shut off and
then restarted. SeeBrake System Warning Light
on page 3-43.
3-44

Traction Off Light
If you have the Traction
Assist System, this light
should come on briey
when you turn the ignition
to RUN.
If the light doesn’t come on then, the system may
require service; have it xed so it will be there to warn
you if the system is turned off.
If the light stays on, or comes on when you’re driving,
there may be a problem with your Traction Assist
System and your vehicle may need service. When this
light is on, the system will not limit wheel spin. Adjust
your driving accordingly.
The traction off light may come on for the following
reasons:
If you turn the system off by pressing the TAS
on/off button located to the left of the steering wheel,
the light will come on and stay on. To turn the
system back on, press the button again; the light
should go off.
If you move the shift lever to FIRST (1), the light
will come on and stay on to indicate that the
traction system is off. This is normal operation.
To turn the system back on, move the shift lever
back to a position other than FIRST (1); the
light should go off. SeeTraction Assist System
(TAS) on page 4-8.
The light will come on and stay on if the TAS
automatic engagement feature has been turned off.
To turn the system on, press the TAS off/on
button; the light should go off. To turn the automatic
engagement feature back on, seeTraction Assist
System (TAS) on page 4-8.
If the Traction Assist System is affected by an
anti-lock brake system, TAS or engine-related
problem, the system will turn off and the light will
come on. Have your vehicle serviced.
If the vehicle is driven over an extremely rough road,
the system will turn off and the light will come on. The
light will go off a few seconds after the rough road
conditions go away or when the vehicle comes to a
complete stop. This is normal operation.
3-45

Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
It also provides an indicator of how hard your vehicle is
working. During a majority of the operation, the gage
will read 210°F (100°C) or less. If you are pulling a load
or going up hills, it is normal for the temperature to
uctuate and approach the 250°F (122°C) mark. If the
gage reaches the 260°F (125°C) mark, it indicates
that the cooling system is working beyond its capacity.
SeeEngine Overheating on page 5-27.
Transmission Temperature Gage
Your vehicle may be equipped with a transmission
temperature gage.
When your ignition is on, the gage shows the
temperature of the transmission uid. The normal
operating range is from 180°F to 200°F (82°C to 93°C).
At approximately 265°F (130°C), the message center
will display a TRANSMISSION HOT message and
the transmission will enter a transmission protection
mode. When the transmission enters the protection
mode, you may notice a change in the transmission
shifting patterns. The transmission will return to normal
shifting patterns when the transmission uid temperature
falls below 260°F (127°C). United States
CanadaUnited StatesCanada
3-46