2005 GMC YUKON XL check engine light

Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments have or
may begin programs to inspect the emission control
equipment on your vehicle. Failure to pass this
inspection could prevent you from getting a vehicle
registration.
Here are some things you need to know to help your
vehicle pass an inspection:
Your vehicle will not pass this inspection if the check
engine light is on or not working properly.
Your vehicle will not pass this inspection if the OBD
(on-board diagnostic) system determines that critical
emission control systems have not been completely
diagnosed by the system. The vehicle would be
considered not ready for inspection. This can happen if
you have recently replaced your battery or if your
battery has run down. The diagnostic system is
designed to evaluate critical emission control systems
during normal driving. This may take several days
of routine driving. If you have done this and your vehicle
still does not pass the inspection for lack of OBD
system readiness, your GM dealer can prepare the
vehicle for inspection.
Oil Pressure Gage
The oil pressure gage shows the engine oil pressure
in psi (pounds per square inch) when the engine
is running. Canadian vehicles indicate pressure in
kPa (kilopascals).
Oil pressure may vary with engine speed, outside
temperature and oil viscosity, but readings above the
low pressure zone indicate the normal operating range.United States
Canada
3-42

A reading in the low pressure zone may be caused by a
dangerously low oil level or some other problem
causing low oil pressure. Check your oil as soon as
possible. SeeEngine Oil on page 5-14.
{CAUTION:
Do not keep driving if the oil pressure is low. If
you do, your engine can become so hot that it
catches re. You or others could be burned.
Check your oil as soon as possible and have
your vehicle serviced.
Notice:Lack of proper engine oil maintenance may
damage the engine. The repairs would not be
covered by your warranty. Always follow the
maintenance schedule in this manual for changing
engine oil.
Security Light
This light will come on
briey when you turn the
key toward START.
The light will stay on until
the engine starts.
If the light ashes, the Passlock
®system has entered a
tamper mode. If the vehicle fails to start, seePasslock®
on page 2-19.
If the light comes on continuously while driving and
stays on, there may be a problem with the Passlock
®
system. Your vehicle will not be protected by Passlock®,
and you should see your dealer.
Also, seeContent Theft-Deterrent on page 2-17for
additional information regarding the security light.
3-43

This reminder will be repeated if the ignition is on, the
vehicle is in motion, the driver is buckled and the
passenger is still unbuckled and the passenger airbag is
enabled. If the passenger’s seat belt is already
buckled, this message and chime will not come on.
Pressing any of the four DIC buttons, if equipped, will
acknowledge the message and clear it from the DIC
display. If your vehicle is not equipped with the four DIC
buttons, pressing the trip odometer reset stem will
acknowledge the message and clear it from the DIC
display.
BUCKLE SEATBELT
If your vehicle is equipped with the passenger sensing
system, this message reminds you to buckle the
driver’s seat belt. SeePassenger Sensing System on
page 1-79.
This message will display and a chime will sound when
the ignition is on, the driver’s seat belt is unbuckled
and the vehicle is in motion. You should buckle
your seat belt.
If the driver remains unbuckled when the ignition is on
and the vehicle is in motion, the reminder will be
repeated. If the driver’s seat belt is already buckled, this
message and chime will not come on.This message is an additional reminder to the Safety
Belt Reminder Light in the instrument panel cluster. See
Safety Belt Reminder Light on page 3-30.
Pressing any of the four DIC buttons, if equipped, will
acknowledge the message and clear it from the
DIC display. If your vehicle is not equipped with the
four DIC buttons, pressing the trip odometer reset stem
will acknowledge the message and clear it from the
DIC display.
CHANGE ENGINE OIL
This message is displayed when the engine oil needs to
be changed. SeeEngine Oil Life System on page 5-17for
information on how to reset the message. This message
will clear itself after 10 seconds until the next ignition
cycle. SeeScheduled Maintenance on page 6-4and
Engine Oil on page 5-14for more information.
CHARGING SYSTEM FAILURE
On some vehicles, if there is a problem with the generator
and battery charging system, this message will appear on
the DIC, a chime will sound and the charging system light
on the instrument panel cluster will come on. See
Charging System Light on page 3-33andVoltmeter Gage
on page 3-34for more information. Driving with this
problem could drain your battery. Turn off all unnecessary
accessories. Stop and turn off the vehicle as soon as it is
safe to do so. Have the electrical system checked by your
GM dealer immediately.
3-51

STABILITY SYS DISABLED
The STABILITY SYS DISABLED message will turn on
when you press the StabiliTrak®button, or when the
stability control has been automatically disabled. To limit
wheel spin and realize the full benets of the stability
enhancement system, you should normally leave
StabiliTrak
®on. However, you should turn StabiliTrak®off
if your vehicle gets stuck in sand, mud, ice or snow and
you want to “rock” your vehicle to attempt to free it, or if
you are driving in extreme off-road conditions and require
more wheel spin. SeeIf You Are Stuck: In Sand, Mud, Ice
or Snow on page 4-42. To turn the StabiliTrak
®system
back on, press the StabiliTrak®button again.
There are four conditions that can cause this message
to appear.
One condition is overheating, which could occur if
StabiliTrak®activates continuously for an extended
period of time.
The message will also be displayed if the brake
system warning light is on. SeeBrake System
Warning Light on page 3-34.
The message could be displayed if the stability
system takes longer than usual to complete its
diagnostic checks due to driving conditions.
Also, if an engine or vehicle related problem has
been detected, and the vehicle needs service,
the message will appear. See your GM dealer.
The message will turn off as soon as the conditions that
caused the message to be displayed are no longer
present.
TIGHTEN FUEL CAP
If the vehicle’s fuel cap is not tightened properly, this
message may appear along with the check engine light
on the instrument panel cluster. SeeMalfunction
Indicator Lamp on page 3-39. Reinstall the fuel cap
fully. SeeFilling Your Tank on page 5-8. The diagnostic
system can determine if the fuel cap has been left off
or improperly installed. A loose or missing fuel cap
will allow fuel to evaporate into the atmosphere. A few
driving trips with the cap properly installed should
turn this light and message off.
3-58

Avoid needless heavy braking. Some people drive in
spurts — heavy acceleration followed by heavy
braking — rather than keeping pace with traffic. This is
a mistake. Your brakes may not have time to cool
between hard stops. Your brakes will wear out much
faster if you do a lot of heavy braking. If you keep pace
with the traffic and allow realistic following distances,
you will eliminate a lot of unnecessary braking.
That means better braking and longer brake life.
If your engine ever stops while you are driving, brake
normally but do not pump your brakes. If you do,
the pedal may get harder to push down. If your engine
stops, you will still have some power brake assist.
But you will use it when you brake. Once the power
assist is used up, it may take longer to stop and
the brake pedal will be harder to push.Anti-Lock Brake System (ABS)
Your vehicle has anti-lock brakes. ABS is an advanced
electronic braking system that will help prevent a
braking skid.
When you start your engine and begin to drive away,
your anti-lock brake system will check itself. You
may hear a momentary motor or clicking noise while
this test is going on. This is normal.
If there is a problem with
the anti-lock brake system,
this warning light will
stay on. SeeAnti-Lock
Brake System Warning
Light on page 3-36.
Along with ABS, your vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights will come on
accompanied by a 10-second chime. The lights and
chime will come on each time the ignition is turned on
until the problem is repaired. See your dealer for service.
4-6

{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You cannot see it
or smell it, so you might not know it is in your
vehicle. Clear away snow from around the
base of your vehicle, especially any that is
blocking your exhaust pipe. And check around
again from time to time to be sure snow does
not collect there.
Open a window just a little on the side of the
vehicle that is away from the wind. This will
help keep CO out.Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little
faster than just idle. That is, push the accelerator
slightly. This uses less fuel for the heat that you get and
it keeps the battery charged. You will need a
well-charged battery to restart the vehicle, and possibly
for signaling later on with your headlamps. Let the
heater run for a while.
Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine
again and repeat this only when you feel really
uncomfortable from the cold. But do it as little as
possible. Preserve the fuel as long as you can. To help
keep warm, you can get out of the vehicle and do
some fairly vigorous exercises every half hour or so until
help comes.
4-41

Notice:Use of automatic transmission uid labeled
other than DEXRON®-III, Approved for the
H-Specication, may damage your vehicle, and the
damages may not be covered by your warranty.
Always use automatic transmission uid labeled
DEXRON
®-III, Approved for the H-Specication.
After adding uid, recheck the uid level as
described under “How to Check,” earlier in
this section.
When the correct uid level is obtained, push the
dipstick back in all the way; then ip the handle
down to lock the dipstick in place.
Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is designed
to remain in your vehicle for ve years or 150,000 miles
(240 000 km), whichever occurs rst, if you add only
DEX-COOL
®extended life coolant.
The following explains your cooling system and how to
add coolant when it is low. If you have a problem with
engine overheating, seeEngine Overheating on
page 5-28.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they
should.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core or radiator
corrosion. In addition, the engine coolant may
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your vehicle.
5-25

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 the off position to
the on position four times within three 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 OFF.
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.
5-65