2001 GMC YUKON XL DENALI ignition

2-42 Dome Lamps
The dome lamps will come on when you open a door
and will slowly dim to off when all doors are closed.
You can also turn the dome lamps on by turning the
thumbwheel, located next to the parking/headlamps
knob, all the way up. In this position, the dome lamps
will remain on whether a door is opened or closed.
You can use the DOME OVERRIDE button, located
below the parking/headlamp knob, to set the dome
lamps to come on automatically when a door is opened,
or remain off. To turn the lamps off, press the button
into the ªinº position. With the button in this position,
the dome lamps will remain off when the doors are
open. To return the lamps to automatic operation, press
the button again and return it to the ªoutº position. With
the button in this position, the dome lamps will come on
when you open a door.
Battery Run-Down Protection
This feature shuts off the dome, reading, glove box
and underhood lamps if they are left on for more than
20 minutes when the ignition is off. This will keep your
battery from running down.
Mirrors
Electrochromic Inside Rearview Mirror
with Compass and Temperature Display
When on, an electrochromic mirror automatically dims
to the proper level to minimize glare from lights behind
you after dark.
The mirror also includes a display of both the compass
and the temperature in the upper right corner of the
mirror face. The dual display can be turned on or off by
briefly pressing either the TEMP or COMP button.

2-43
Temperature Display
Pressing the TEMP button once briefly will toggle the
compass/temperature reading on and off. To alternate
the temperature reading between Fahrenheit and Celsius,
press and hold the TEMP button for three seconds until
the display blinks F
and C
. Press and release the
TEMP button to toggle between the Fahrenheit and
Celsius readings. After five seconds of inactivity, the
display will stop flashing and stay at the last setting.
If an abnormal reading is displayed, please consult
your dealer.Electrochromic Mirror Operation
The right side of the button, labeled TEMP and located
at the bottom of the mirror, turns the electrochromic
mirror on and off. An indicator light, located to the
right of the TEMP button, will come on when the
electrochromic mirror is turned on. To turn the mirror
on, press and hold the TEMP button for 15 seconds. To
turn the mirror off, press and hold the TEMP button for
15 seconds. The indicator light will turn off.
Compass Operation
With the ignition on, the compass will show
two character boxes. The mirror will display the
compass heading.
When cleaning the mirror, use a paper towel or similar
material dampened with glass cleaner. Do not spray
glass cleaner directly on the mirror as that may cause
the liquid cleaner to enter the mirror housing.

2-57
Sunroof (If Equipped)
Your vehicle may be equipped with a power sliding
sunroof. To open or close your sunroof, the ignition
needs to be on or RAP needs to be active. See ªRetained
Accessory Powerº in the Index.
Press and release the rear side of the button located in
the front overhead console to express
-open the glass
panel and sunshade. To close the glass panel, press and
hold the front of the button. The glass will not be fully
seated unless the button is held until the glass stops
moving. With the sunroof closed, press the forward side
of the button to open the sunroof to the vent position.The sunroof is also equipped with a sunshade which you
can pull forward to block sun rays.
If a hand, arm, or other object is blocking the sunroof
glass panel as it is closing, the glass panel will stop at
the obstruction. After the obstruction is removed, the
glass panel can be closed or opened.
Use care not to leave the sunroof open for long periods
of time as debris may collect in the tracks.
If the battery has been recharged, disconnected or is not
working, you may need to reprogram the sunroof. To do
this, start the vehicle and press the forward side of the
sunroof switch until the glass panel moves to a fully
closed position. Release, and press again to move to the
vent position which occurs when the sunroof is fully
tilted rearward. This will reset the memory and enable
the sunroof to function properly.

2-65 Speedometer and Odometer
Your speedometer lets you see your speed in both
miles per hour (mph) and kilometers per hour (km/h).
Your odometer shows how far your vehicle has been
driven, in either miles (used in the United States) or
kilometers (used in Canada).
Trip Odometer
The trip odometer can tell you how far your vehicle has
been driven since you last set the trip odometer to zero.
Press the reset button to toggle between the trip
odometer and the regular odometer. Holding the reset
button for two seconds while the trip odometer is
displayed will reset it.
To display the odometer reading with the ignition off,
press the reset button.
Engine Hour Meter Display
The odometer can also display the number of hours the
engine has run. To display the hour meter, turn the
ignition off, press and hold the reset button for at least
four seconds. The hour meter will be displayed for up
to 30 seconds, or until the ignition is turned on.
Tachometer
Your tachometer displays the engine speed in
revolutions per minute (rpm).
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 briefly 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.

2-67
CAUTION:
If the air bag readiness light stays on after you
start your vehicle, it means the air bag system
may not be working properly. The air bags in
your vehicle may not inflate in a crash, or they
could even inflate without a crash. To help avoid
injury to yourself or others, have your vehicle
serviced right away if the air bag readiness light
stays on after you start your vehicle.
The air bag readiness light should flash for a
few seconds when you turn the ignition key to RUN.
If the light doesn't come on then, have it fixed so it will
be ready to warn you if there is a problem.
Voltmeter
United States Canada
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. Readings between the
low and high warning zones indicate the normal
operating range.

2-68
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 flash when you set the parking brake. The light
will flash 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, there could be a brake
problem. Have your brake system inspected right away.
United States Canada
This light should come on briefly when you turn the
ignition key to RUN. If it doesn't come on then,
have it fixed so it will be ready to warn you if there's
a problem.

2-69
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, the pedal may go closer to the floor.
It may take longer to stop. If the light is still on, have the
vehicle towed for service. See ªTowing Your Vehicleº in
the Index.
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've
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 stays on, or comes on when you're driving,
your vehicle needs service. 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. See
ªBrake System Warning Lightº earlier in this section.
The anti
-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn't come on then, have it fixed so it will be
ready to warn you if there is a problem.

2-70 Engine Coolant Temperature Gage
United States Canada
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
fluctuate 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.
The ªProblems on the Road,º section of this manual
shows what to do. See ªEngine Overheatingº in
the Index.
Transmission Temperature Gage
United States Canada
When your ignition is on, the gage shows the temperature
of the transmission fluid. The normal operating range is
from 100
F (38
C) to about 265
F (130
C).
At approximately 265
F (130
C), the message center
will display a TRANS FLUID 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 fluid temperature falls
below 260
F (127
C).
See ªMessage Centerº in the Index for further information.