2010 GMC YUKON XL check engine light

Emissions Inspection and Maintenance
Programs
Some state/provincial and local governments may have
programs to inspect the on-vehicle emission control
equipment For the inspection, the emission system
test equipment is connected to the vehicle’s Data Link
Connector (DLC).
The DLC is under the instrument panel to the left of the
steering wheel. See your dealer if assistance is needed.The vehicle may not pass inspection if:
.the check engine light is on with the engine
running, or if the light does not come on when
the ignition is turned to ON/RUN while the engine
is off.
.the critical emission control systems have not been
completely diagnosed by the system. This can
happen if the battery has recently been replaced or
if the battery has run down. The diagnostic system
evaluates critical emission control systems during
normal driving. This can take several days of
routine driving. If this has been done and the
vehicle still does not pass the inspection, your
dealer can prepare the vehicle for inspection.
4-42

Oil Pressure Light
{WARNING:
Do not keep driving if the oil pressure is low.
The engine can become so hot that it catches fire.
Someone could be burned. Check the oil as soon
as possible and have the vehicle serviced.
Notice: Lack of proper engine oil maintenance
can damage the engine. The repairs would not be
covered by the vehicle warranty. Always follow the
maintenance schedule in this manual for changing
engine oil. This light comes on briefly while starting the engine.
If it does not, have the vehicle serviced by your dealer.
If the system is working normally the indicator light then
goes off.
If the light comes on and stays on, it means that oil is
not flowing through the engine properly. The vehicle
could be low on oil and it might have some other
system problem.
Security Light
For information regarding
this light and the vehicle's
security system, see
Content Theft-Deterrent
on page 3‑23.
4-44

There are several 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 also displays if the brake system
warning light is on. SeeBrake System Warning
Light on page 4‑36.
.The message could display if the stability system
takes longer than usual to complete its diagnostic
checks due to driving conditions.
.The message displays if an engine or vehicle
related problem has been detected and the vehicle
needs service. See your dealer.
.The message also displays if the vehicle is shifted
into 4LO (Two Speed Transfer Case Only).
The message turns off as soon as the conditions that
caused the message to be displayed are no longer
present.
TIGHTEN GAS CAP
This message may display along with the check engine
light on the instrument panel cluster if the vehicle's fuel
cap is not tightened properly. See Malfunction Indicator
Lamp
on page 4‑39. Reinstall the fuel cap fully.
See Filling the Tankon page 6‑11. The diagnostic
system can determine if the fuel cap has been left off or
improperly installed. A loose or missing fuel cap allows
fuel to evaporate into the atmosphere. A few driving
trips with the cap properly installed should turn this light
and message off.
TIRE LEARNING ACTIVE
On vehicles with the Tire Pressure Monitor System
(TPMS), this message displays when the TPMS is
re-learning the tire positions on your vehicle. The tire
positions must be re-learned after rotating the tires or
after replacing a tire or sensor. See Tire Inspection and
Rotation
on page 6‑78, Tire Pressure Monitor Systemon page 6‑73, and Inflation - Tire Pressureon
page 6‑72for more information.
4-69

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.
The brakes might not have time to cool between hard
stops. The brakes will wear out much faster with a lot
of heavy braking. Keeping pace with the traffic and
allowing realistic following distances eliminates a lot of
unnecessary braking. That means better braking and
longer brake life.
If the engine ever stops while the vehicle is being
driven, brake normally but do not pump the brakes.
If the brakes are pumped, the pedal could get harder to
push down. If the engine stops, there will still be some
power brake assist but it will be used when the brake is
applied. Once the power assist is used up, it can take
longer to stop and the brake pedal will be harder
to push.
Adding non‐dealer/non‐retailer accessories can
affect vehicle performance. SeeAccessories and
Modifications on page 6‑4.Antilock Brake System (ABS)
This vehicle has the Antilock Brake System (ABS), an
advanced electronic braking system that helps prevent
a braking skid.
When the engine is started and the vehicle begins to
drive away, ABS checks itself. A momentary motor or
clicking noise might be heard while this test is going on.
This is normal.
If there is a problem with
ABS, this warning light
stays on. See Antilock
Brake System (ABS)
Warning Light
on
page 4‑37.
Along with ABS, the vehicle has a Dynamic Rear
Proportioning (DRP) system. If there is a DRP problem,
both the brake and ABS warning lights 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.
5-4

Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine
3. Shift into a gear
4. Release the parking brake
5. Let up on the brake pedal.
6. Drive slowly until the trailer is clear of the chocks.
7. Stop and have someone pick up and store thechocks.
Maintenance When Trailer Towing
The vehicle needs service more often when pulling a
trailer. See this manual's Maintenance Schedule or
Index for more information. Things that are especially
important in trailer operation are automatic transmission
fluid, engine oil, axle lubricant, belts, cooling system
and brake system. It is a good idea to inspect these
before and during the trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
The vehicle is equipped with the following wiring
harnesses for towing a trailer.
Basic Trailer Wiring
The trailer wiring harness, with a seven-pin connector,
is located at the rear of the vehicle and is tied to the
vehicle's frame. The harness connector can be plugged
into a seven-pin universal heavy-duty trailer connector
available through your dealer.
The seven-wire harness contains the following trailer
circuits:
.Yellow: Left Stop/Turn Signal
.Dark Green: Right Stop/Turn Signal
.Brown: Taillamps
.White: Ground
.Light Green: Back-up Lamps
.Red: Battery Feed*
.Dark Blue: Trailer Brake*
*The fuses for these two circuits are installed in the
underhood electrical center, but the wires are not
connected. They should be connected by your dealer
or a qualified service center.
5-67

Brakes
Brake Fluid
The brake master cylinder
reservoir is filled with
DOT 3 brake fluid. See
Engine Compartment
Overview
on page 6‑16for the location of the
reservoir.
There are only two reasons why the brake fluid level in
the reservoir might go down:
.The brake fluid level goes down because of normal
brake lining wear. When new linings are installed,
the fluid level goes back up.
.A fluid leak in the brake hydraulic system can also
cause a low fluid level. Have the brake hydraulic
system fixed, since a leak means that sooner or
later the brakes will not work well. Do not top off the brake fluid. Adding fluid does not
correct a leak. If fluid is added when the linings are
worn, there will be too much fluid when new brake
linings are installed. Add or remove brake fluid, as
necessary, only when work is done on the brake
hydraulic system.
{WARNING:
If too much brake fluid is added, it can spill on
the engine and burn, if the engine is hot enough.
You or others could be burned, and the vehicle
could be damaged. Add brake fluid only when
work is done on the brake hydraulic system.
See
“Checking Brake Fluid” in this section.
When the brake fluid falls to a low level, the brake
warning light comes on. See Brake System Warning
Light on page 4‑36.
Refer to the Maintenance Schedule to determine when
to check the brake fluid. See Scheduled Maintenance
on page 7‑3.
6-42

A
Accessories and Modifications . . . . . . . . . . . . . . . . . . . . . . .6-4
Accessory Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-29
Accessory Power Outlets . . . . . . . . . . . . . . . . . . . . . . . . . . 4-16
Active Fuel Management™. . . . . . . . . . . . . . . . . . . . . . . . 3-33
Add-On Electrical Equipment . . . . . . . . . . . . . . . . . . . . . 6-118
Adding a Snow Plow or Similar Equipment . . . . . . . . 5-37
Additives, Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-8
Adjustable Throttle and Brake Pedal . . . . . . . . . . . . . . . 3-31
Air Cleaner/Filter, Engine . . . . . . . . . . . . . . . . . . . . . . . . . . 6-22
Air Conditioning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-18
Airbag Adding Equipment to Your Airbag-EquippedVehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-100
Airbag System How Does an Airbag Restrain? . . . . . . . . . . . . . . . . . . . 2-91
Passenger Sensing System . . . . . . . . . . . . . . . . . . . . . . 2-94
Servicing Your Airbag-Equipped Vehicle . . . . . . . . . . 2-99
What Makes an Airbag Inflate? . . . . . . . . . . . . . . . . . . . 2-91
What Will You See After an Airbag Inflates? . . . . . . 2-92
When Should an Airbag Inflate? . . . . . . . . . . . . . . . . . . 2-89
Where Are the Airbags? . . . . . . . . . . . . . . . . . . . . . . . . . . 2-86
Airbags Passenger Status Indicator . . . . . . . . . . . . . . . . . . . . . . . 4-33
Readiness Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-32
System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-83 Antenna
Rear Side Window . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-140
Antenna, XM™ Satellite Radio Antenna
System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-140
Antilock Brake System (ABS) . . . . . . . . . . . . . . . . . . . . . . . .5-4 Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-37
Appearance Care
Aluminum or Chrome-Plated Wheels . . . . . . . . . . . . 6-114
Care of Safety Belts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-111
Chemical Paint Spotting . . . . . . . . . . . . . . . . . . . . . . . . . 6-116
Cleaning Exterior Lamps/Lenses . . . . . . . . . . . . . . . . 6-112
Fabric/Carpet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-109
Finish Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-113
Finish Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-116
Instrument Panel, Vinyl, and Other PlasticSurfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-111
Interior Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-108
Leather . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-110
Sheet Metal Damage . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
Underbody Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . 6-116
Washing Your Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-112
Weatherstrips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-111
Windshield, Backglass, and Wiper Blades . . . . . . . 6-114
Ashtray . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-17
Assistance Program, Roadside . . . . . . . . . . . . . . . . . . . . . .8-7
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C
Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-58
CaliforniaPerchlorate Materials Requirements . . . . . . . . . . . . . . . 6-5
Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-5
California Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-8
Camera, Rear Vision . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-64
Canadian Owners . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii
Capacities and Specifications . . . . . . . . . . . . . . . . . . . . . 6-126
Carbon Monoxide . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-13, 3-15 Engine Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-52
Winter Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5-27
Care of Safety Belts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-111
Cargo Cover . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-78
CD, MP3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-99, 4-106
Center Console Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-76
Center Seat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-15
Chains, Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-86
Charging System Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-34
Check Engine Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-39
Checking Things Under the Hood . . . . . . . . . . . . . . . . . . 6-14
Chemical Paint Spotting . . . . . . . . . . . . . . . . . . . . . . . . . . 6-116 Child Restraints
Infants and Young Children . . . . . . . . . . . . . . . . . . . . . . . 2-59
Lower Anchors and Tethers for Children . . . . . . . . . . 2-67
Older Children . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-55
Securing a Child Restraint in a Rear Seat
Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-75
Securing a Child Restraint in the Center Front
Seat Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-79
Securing a Child Restraint in the Right Front Seat Position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-79
Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-63
Where to Put the Restraint . . . . . . . . . . . . . . . . . . . . . . . 2-65
Cigarette Lighter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-17
Circuit Breakers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-118
Cleaning Aluminum or Chrome-Plated Wheels . . . . . . . . . . . . 6-114
Exterior Lamps/Lenses . . . . . . . . . . . . . . . . . . . . . . . . . . 6-112
Fabric/Carpet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-109
Finish Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-113
Instrument Panel, Vinyl, and Other PlasticSurfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-111
Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-108
Leather . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-110
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-115
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