2008 GMC SIERRA check engine light

You can run the engine to keep warm, but be careful.
{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 the 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 the headlamps. Let the
heater run for a while.
4-33

Turn Signals When Towing a Trailer
The arrows on your instrument panel will ash whenever
you signal a turn or lane change. Properly hooked up,
the trailer lamps will also ash, telling other drivers
you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your instrument
panel will ash for turns even if the bulbs on the trailer
are burned out. Thus, you may think drivers behind
you are seeing your signal when they are not. It’s
important to check occasionally to be sure the trailer
bulbs are still working.
Driving On Grades
Reduce speed and shift to a lower gearbeforeyou start
down a long or steep downgrade. If you don’t shift
down, you might have to use your brakes so much that
they would get hot and no longer work well.You can tow in DRIVE (D). You may want to shift the
transmission to lower gear selection if the transmission
shifts too often (e.g., under heavy loads and/or hilly
conditions).
You may also want to activate the tow/haul mode if the
transmission shifts too often. SeeTow/Haul Mode
Light on page 3-53.
When towing at high elevation on steep uphill grades,
consider the following: Engine coolant at higher
elevations will boil at a lower temperature than at or
near sea level. If you turn your engine off immediately
after towing at high elevation on steep uphill grades,
your vehicle may show signs similar to engine
overheating. To avoid this, let the engine run while
parked, preferably on level ground, with the transmission
in PARK (P) at least ve minutes before turning the
engine off. If you do get the overheat warning, see
Engine Overheating on page 5-30.
4-88

When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
Start your engine
Shift into a gear
Release the parking brake
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. SeeScheduled Maintenance (Gasoline
Engine) on page 6-4for more information. Things
that are especially important in trailer operation are
automatic transmission uid (don’t overll), engine oil,
axle lubricant, belt, cooling system and brake system.
Each of these is covered in this manual, and the Index
will help you nd them quickly. If you’re trailering, it’s
a good idea to review these sections before you
start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Trailer Wiring Harness
Your vehicle is equipped with one of the following wiring
harnesses for towing a trailer or hauling a slide-in
camper.
Basic Trailer Wiring
All regular, extended cab and crew cab pickups have a
seven-wire trailer towing harness.
For vehicles not equipped with heavy duty trailering, the
harness is clipped to the vehicle’s frame behind the
spare tire mount. The harness requires the installation
of a trailer connector, which is available through
your dealer.
If you need to tow a light-duty trailer with a standard
four-way round pin connector, you can also get an
adapter from your dealer.
4-90

(e)Make sure the safety belt reminder light and safety
belt assemblies are working properly. Look for any
other loose or damaged safety belt system parts. If you
see anything that might keep a safety belt system
from doing its job, have it repaired. Have any torn or
frayed safety belts replaced. Also see Checking
the Restraint Systems on page 1-87.
(f)Lubricate all key lock cylinders, body door hinges,
hood latch assembly, secondary latch, pivots, spring
anchor, release pawl, tailgate hinges, tailgate linkage,
tailgate handle pivot points, latch bolt, fuel door
hinge, locks, and folding seat hardware. More frequent
lubrication may be required when exposed to a
corrosive environment. Applying silicone grease on
weatherstrips with a clean cloth will make them
last longer, seal better, and not stick or squeak.
(g)Check vent hose at transfer case for kinks and
proper installation. Check to be sure vent hose
is unobstructed, clear, and free of debris.(h)Change automatic transmission fluid and filter if the
vehicle Gross Vehicle Weight Rating (GVWR) is
over 8600 lbs or if the vehicle is mainly driven under
one or more of these conditions:
In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery
service.
(i)Drain, flush, and refill cooling system. This service can
be complex; you should have your dealer/retailer perform
this service. See Engine Coolant on page 5-28for what to
use. Inspect hoses. Clean radiator, condenser, pressure
cap, and ller neck. Pressure test the cooling system and
pressure cap.
(j)A fluid loss in any vehicle system could indicate a
problem. Have the system inspected and repaired and
the fluid level checked. Add fluid if needed.
(k)Inspect system. Check all fuel and vapor lines and
hoses for proper hook-up, routing, and condition. Check
that the purge valve, if the vehicle has one, works
properly. Replace as needed.
6-10

Center High-Mounted Stoplamp (CHMSL) and
Cargo Lamp...............................................5-61
Center Seat...................................................1-12
Chains, Tire...................................................5-90
Charging System Light....................................3-43
Check
Engine Light...............................................3-48
Checking Things Under the Hood......................5-12
Chemical Paint Spotting.................................5-120
Child Restraints
Child Restraint Systems...............................1-42
Infants and Young Children...........................1-38
Lower Anchors and Tethers for Children..........1-45
Older Children.............................................1-35
Securing a Child Restraint in a Rear
Seat Position...........................................1-55
Securing a Child Restraint in the Center
Front Seat Position...................................1-57
Securing a Child Restraint in the Right Front
Seat Position...........................1-58, 1-62, 1-66
Where to Put the Restraint...........................1-44
Cigarette Lighter.............................................3-24
Cleaning
Aluminum or Chrome-Plated Wheels.............5-118
Exterior Lamps/Lenses................................5-116
Fabric/Carpet............................................5-114
Finish Care...............................................5-116
Instrument Panel, Vinyl, and Other Plastic
Surfaces...............................................5-115Cleaning (cont.)
Interior.....................................................5-112
Leather....................................................5-114
Tires........................................................5-119
Underbody Maintenance.............................5-119
Washing Your Vehicle.................................5-116
Weatherstrips............................................5-115
Windshield and Wiper Blades......................5-117
Climate Control System...........................3-25, 3-27
Dual Automatic............................................3-28
Outlet Adjustment........................................
3-33
Clock, Setting.................................................3-81
Collision Damage Repair..................................7-11
Compass...............................................2-55, 2-57
Content Theft-Deterrent....................................2-18
Control of a Vehicle.......................................... 4-3
Coolant
Engine Temperature Gage............................3-46
Heater, Engine............................................2-26
Surge Tank Pressure Cap.............................5-30
Cooling System..............................................5-34
Cruise Control................................................3-14
Cruise Control Light........................................3-52
Cupholder(s)..................................................2-75
Customer Assistance Information
Courtesy Transportation.................................. 7-9
Customer Assistance for Text
Telephone (TTY) Users............................... 7-5
Customer Assistance Offices........................... 7-5
3

Electrical System (cont.)
Instrument Panel Fuse Block.......................5-124
Power Windows and Other Power Options....5-123
Underhood Fuse Block...............................5-126
Windshield Wiper Fuses.............................5-123
Engine
Air Cleaner/Filter.........................................5-19
Check and Service Engine Soon Light............3-48
Coolant......................................................5-28
Coolant Heater............................................2-26
Coolant Temperature Gage...........................3-46
Drive Belt Routing.......................................6-18
Engine Compartment Overview......................5-14
Exhaust.....................................................2-53
Fan Noise..................................................5-39
Fast Idle System.........................................2-25
Oil .............................................................5-15
Oil Life System...........................................5-18
Overheated Protection Operating Mode...........5-33
Overheating................................................5-30
Running While Parked..................................2-54
Starting......................................................2-24
Entry Lighting.................................................3-21
Event Data Recorders.....................................7-17
Exit Lighting...................................................3-21
Extender, Safety Belt.......................................1-35
Exterior Lamps...............................................3-17F
Fast Idle System............................................2-25
Filter
Engine Air Cleaner......................................5-19
Finish Damage.............................................5-119
Fixed Mast Antenna.......................................3-126
Flashers, Hazard Warning.................................. 3-8
Flash-to-Pass.................................................3-11
Flat Tire........................................................5-91
Flat Tire, Changing.........................................5-92
Flat Tire, Storing...........................................5-108
Fluid.....................................................5-22, 5-25
Power Steering...........................................5-39
Windshield Washer......................................5-40
Fog Lamp
Fog ...........................................................3-20
Fog Lamp Light..............................................3-52
Four-Wheel Drive....................................2-36, 5-52
Four-Wheel-Drive Light....................................3-53
Front Axle......................................................5-54
Fuel............................................................... 5-6
Additives...................................................... 5-7
California Fuel.............................................. 5-7
E85 (85% Ethanol)........................................ 5-8
Filling a Portable Fuel Container....................5-12
Filling the Tank...........................................5-10
5

Fuel (cont.)
Fuels in Foreign Countries.............................. 5-9
Gage.........................................................3-53
Gasoline Octane........................................... 5-6
Gasoline Specications.................................. 5-6
Low Warning Light.......................................3-54
Fuses
Center Instrument Panel Fuse Block.............5-125
Fuses and Circuit Breakers.........................5-123
Instrument Panel Fuse Block.......................5-124
Underhood Fuse Block...............................5-126
Windshield Wiper.......................................5-123
G
Gage
Engine Coolant Temperature.........................3-46
Fuel..........................................................3-53
Oil Pressure...............................................3-50
Speedometer..............................................3-36
Tachometer.................................................3-36
Voltmeter Gage...........................................3-43
Garage Door Opener.......................................2-68
Gasoline
Octane........................................................ 5-6
Specications............................................... 5-6
Glove Box.....................................................2-74
GM Mobility Reimbursement Program.................. 7-6
H
Hazard Warning Flashers................................... 3-8
Head Restraints..............................................1-10
Headlamp
Aiming.......................................................5-56
Headlamps....................................................5-60
Bulb Replacement.......................................5-59
Daytime Running Lamps...............................3-18
Exterior Lamps............................................3-17
Flash-to-Pass..............................................3-11
Halogen Bulbs............................................5-59
High/Low Beam Changer..............................3-11
On Reminder..............................................3-18
Pickup Box Identication and Fender
Marker Lamps.........................................5-62
Heated Seats................................................... 1-6
Heater...................................................3-25, 3-27
Heater...........................................................3-28
Highbeam On Light.........................................3-52
Highway Hypnosis...........................................4-29
Hill and Mountain Roads..................................4-30
Hood
Checking Things Under................................5-12
Release.....................................................5-13
Horn............................................................... 3-8
How to Wear Safety Belts Properly...................1-19
6

Mirrors
Automatic Dimming Rearview with Compass
and Temperature Display...........................2-57
Automatic Dimming Rearview with OnStar
®,
Compass and Temperature Display.............2-55
Manual Rearview Mirror................................2-55
Outside Manual Mirrors................................2-58
Outside Power Foldaway Mirrors....................2-61
Outside Power Mirrors..................................2-59
Outside Trailer-Tow Mirrors...........................2-59
MP3 ..................................................3-102, 3-106
MyGMLink.com................................................ 7-4
N
Navigation System, Privacy..............................7-18
Navigation/Radio System, see Navigation
Manual.....................................................3-112
New Vehicle Break-In......................................2-22
Noise Control System, Tampering......................5-56
O
Odometer......................................................3-36
Odometer, Trip...............................................3-36
Off-Road Driving.............................................4-12Off-Road Recovery..........................................4-10
Oil
Engine.......................................................5-15
Pressure Gage............................................3-50
Pressure Light.............................................3-51
Oil, Engine Oil Life System..............................5-18
Older Children, Restraints................................1-35
Online Owner Center........................................ 7-4
OnStar, Privacy..............................................7-18
OnStar
®System, see OnStar®Manual...............2-65
Operation, Universal Home Remote System........2-69
Other Warning Devices...................................... 3-8
Outlet Adjustment............................................3-33
Outlets
Accessory Power.........................................3-23
Outside
Manual Mirrors............................................2-58
Power Foldaway Mirrors...............................2-61
Power Mirrors.............................................2-59
Trailer-Tow Mirrors.......................................2-59
Overheated Engine Protection
Operating Mode..........................................5-33
Owner Checks and Services.............................6-11
Owners, Canadian............................................... ii
9