2007 GMC SIERRA CLASSIC heater

What to Use
Use a mixture of one-half clean, drinkable water
and one-half DEX-COOL®coolant which will
not damage aluminum parts. If you use this coolant
mixture, you do not need to add anything else.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.Notice:If you use an improper coolant
mixture, your engine could overheat and be
badly damaged. The repair cost would not be
covered by your warranty. Too much water
in the mixture can freeze and crack the engine,
radiator, heater core, and other parts.
If you have to add coolant more than four times a
year, have your dealer check your cooling
system.
Notice:If you use extra inhibitors and/or
additives in your vehicle’s cooling system,
you could damage your vehicle. Use only the
proper mixture of the engine coolant listed
in this manual for the cooling system.
SeeRecommended Fluids and Lubricants
on page 629for more information.
503

If No Steam Is Coming From Your
Engine
The ENGINE COOLANT HOT message, along
with a low coolant condition, can indicate a serious
problem.
If you get an engine overheat warning, but see or
hear no steam, the problem may not be too
serious. Sometimes the engine can get a little too
hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. SeeTowing a Trailer on
page 429.
If you get the ENGINE COOLANT HOT message
with no sign of steam, try this for a minute or so:
1. If your air conditioner is on, turn it off.
2. Turn on your heater to full hot at the highest
fan speed and open the windows as
necessary.
3. If you are in a traffic jam, shift to
NEUTRAL (N); otherwise, shift to the highest
gear while driving — DRIVE (D) or THIRD (3).If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not come
back on, you can drive normally.
If the warning continues, pull over, stop, park, and
fast idle your vehicle right away.
If there is still no sign of steam and your vehicle
is equipped with an engine-driven cooling fan,
push down the accelerator until the engine speed
is about twice as fast as normal idle speed for
at least three minutes while you are parked.
If there is still no sign of steam and your vehicle is
equipped with an electric engine cooling fan, idle
the engine for three minutes while you are parked.
If you still have the warning, turn off the engine
and get everyone out of the vehicle until it
cools down. Also, see “Overheated Engine
Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get
service help right away.
507

The coolant level should
be at or above the FULL
COLD mark. If it is not,
you may have a leak at
the pressure cap or in
the radiator hoses,
heater hoses, radiator,
water pump, or
somewhere else in the
cooling system.
{CAUTION:
Heater and radiator hoses, and other
engine parts, can be very hot. Do not
touch them. If you do, you can be burned.
Do not run the engine if there is a leak.
If you run the engine, it could lose all
coolant. That could cause an engine re,
and you could be burned. Get any leak
xed before you drive the vehicle.If your vehicle has an electric engine cooling
fan, check the coolant temperature gage.
If the coolant temperature is approximately
232°F (111°C), the electric cooling fan should be
running. If it is not, your vehicle needs service.
Turn off the engine.
If your vehicle has an engine-driven cooling fan,
start the engine again and see if the fan speed
increases when idle speed is doubled by pushing
the accelerator pedal down. If it does not, your
vehicle needs service. Turn off the engine.
Notice:Engine damage from running your
engine without coolant is not covered by your
warranty. SeeOverheated Engine Protection
Operating Mode (V8 Engines Only) on page 508
for information on driving to a safe place in
an emergency.
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.
510

{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can
boil before the proper coolant mixture will.
Your vehicle’s coolant warning system is
set for the proper coolant mixture. With
plain water or the wrong mixture, your
engine could get too hot but you would
not get the overheat warning. Your engine
could catch re and you or others could
be burned. Use a 50/50 mixture of clean,
drinkable water and a proper coolant.
Notice:In cold weather, water can freeze and
crack the engine, radiator, heater core and
other parts. Use the recommended coolant and
the proper coolant mixture.
{CAUTION:
You can be burned if you spill coolant
on hot engine parts. Coolant contains
ethylene glycol and it will burn if the
engine parts are hot enough. Do not spill
coolant on a hot engine.
1. You can remove the
coolant surge tank
pressure cap when
the cooling system,
including the coolant
surge tank pressure
cap and upper
radiator hose, is no
longer hot.
Turn the pressure cap slowly counterclockwise
about one full turn. If you hear a hiss, wait
for that to stop. A hiss means there is
still some pressure left.
512

1*Fuel Injection Rail #2-Gasoline Engine; Engine
Control Module-Diesel Engine.
2*Fuel Injection Rail #1-Gasoline Engine;
Actuator-Diesel Engine.
3*Oxygen Sensors-Gasoline Engine; Fuel
Heater-Diesel Engine.
4*Oxygen Sensors-Gasoline Engine; Engine
Control Module 1-Diesel Engine.
5*Ignition 1-Gasoline Engine; Engine Control
Module-Diesel Engine.
6*Powertrain Control Module B-Gasoline Engine;
Engine Control Module B-Diesel Engine.
7*Supplemental Brake Assist - Gasoline Engine;
Electronic Viscous Fan - Diesel Engine.
8*Rear Climate Control.
9*Sunroof.Fuses Usage
GLOW PLUGDiesel Glow Plugs and Intake
Air Heater
CUST FEED Gasoline Accessory Power
HYBRID Hybrid
STUD #1Auxiliary Power (Single
Battery and Diesels Only)/
Dual Battery (TP2) Do not
install fuse.
MBECMid Bussed Electrical Center
Power Feed, Front Seats,
Right Doors
BLWR Front Climate Control Fan
LBECLeft Bussed Electrical Center,
Door Modules, Door Locks,
Auxiliary Power Outlet—Rear
Cargo Area and Instrument
Panel
STUD #2*Accessory Power/Trailer
Wiring Brake Feed
ABS Anti-lock Brakes
VSES/ECAS Vehicle Stability
IGN A Ignition Power
IGN B Ignition Power
605

Cigarette Lighter.......................................... 229
Cleaning
Aluminum or Chrome-Plated Wheels........ 594
Exterior Lamps/Lenses............................. 593
Fabric/Carpet........................................... 590
Finish Care.............................................. 593
Inside of Your Vehicle.............................. 589
Instrument Panel, Vinyl, and Other
Plastic Surfaces.................................... 591
Leather.................................................... 591
Tires........................................................ 595
Underbody Maintenance........................... 596
Washing Your Vehicle.............................. 592
Weatherstrips........................................... 592
Windshield and Wiper Blades................... 594
Climate Control System............................... 230
Dual......................................................... 231
Dual Automatic......................................... 235
Outlet Adjustment..................................... 243
Clutch, Hydraulic......................................... 501
Collision Damage Repair............................. 651
Comfort Guides, Rear Safety Belt................. 41
Compass............................................176, 180
Content Theft-Deterrent............................... 131
Control of a Vehicle..................................... 360Coolant
Engine Temperature Gage........................ 256
Heater, Engine......................................... 139
Surge Tank Pressure Cap........................ 505
Cooling System........................................... 508
Cruise Control............................................. 217
Cruise Control Light.................................... 263
Cupholder(s)................................................ 202
Customer Assistance Information
Courtesy Transportation........................... 647
Customer Assistance for Text
Telephone (TTY) Users ......................... 642
Customer Assistance Offices.................... 642
Customer Satisfaction Procedure.............. 638
GM Mobility Reimbursement Program...... 643
Reporting Safety Defects to General
Motors.................................................. 656
Reporting Safety Defects to the
Canadian Government.......................... 656
Reporting Safety Defects to the
United States Government.................... 656
Roadside Assistance Program.................. 644
Service Publications Ordering
Information........................................... 657
662

Engine (cont.)
Check and Service Engine Soon Light..... 258
Coolant.................................................... 502
Coolant Heater......................................... 139
Coolant Temperature Gage...................... 256
Drive Belt Routing.................................... 633
Engine Compartment Overview................ 480
Exhaust................................................... 174
Fan Noise................................................ 514
Oil ........................................................... 486
Oil Life System........................................ 489
Overheated Protection Operating Mode.... 508
Overheating............................................. 505
Starting.................................................... 137
Entry Lighting.............................................. 227
Event Data Recorders (EDR)...................... 650
Exit Lighting................................................ 227
Extender, Safety Belt..................................... 43
F
Filter
Engine Air Cleaner................................... 491
Finish Damage............................................ 596
Fixed Mast Antenna.................................... 353
Flashers, Hazard Warning........................... 212Flash-to-Pass.............................................. 216
Flat Tire...................................................... 563
Flat Tire, Changing...................................... 564
Flat Tire, Storing......................................... 584
Fluid
Automatic Transmission...................494, 497
Manual Transmission................................ 500
Power Steering........................................ 515
Windshield Washer.................................. 516
Fog Lamps.................................................. 225
Four-Wheel Drive...............................153, 528
Four-Wheel-Drive Light................................ 263
Front Axle................................................... 529
Front Reading Lamps.................................. 227
Front Storage Area...................................... 202
Fuel............................................................ 470
Additives.................................................. 472
California Fuel.......................................... 471
E85 (85% Ethanol)................................... 473
Filling a Portable Fuel Container.............. 477
Filling Your Tank...................................... 474
Fuels in Foreign Countries....................... 474
Gage....................................................... 264
Gasoline Octane...................................... 470
Gasoline Specications............................ 471
Low Warning Light................................... 265
664

Fuses
Center Instrument Panel Fuse Block........ 602
Fuses and Circuit Breakers...................... 600
Instrument Panel Fuse Block................... 600
Underhood Fuse Block............................. 603
Windshield Wiper..................................... 599
G
Gage
Engine Coolant Temperature.................... 256
Fuel......................................................... 264
Oil Pressure............................................. 262
Speedometer........................................... 246
Tachometer.............................................. 246
Transmission Temperature........................ 257
Voltmeter Gage........................................ 253
Garage Door Opener..........................191, 192
Gasoline
Octane..................................................... 470
Specications........................................... 471
Glove Box................................................... 202
GM Mobility Reimbursement Program.......... 643
H
Hazard Warning Flashers............................ 212
Head Restraints............................................ 18
Headlamps.........................................221, 533
Automatic Headlamp System.................... 223
Bulb Replacement.................................... 532
Daytime Running Lamps.......................... 222
Flash-to-Pass........................................... 216
Front Turn Signal, Sidemarker and
Daytime Running Lamps....................... 534
Halogen Bulbs......................................... 532
High/Low Beam Changer......................... 215
On Reminder........................................... 222
Pickup Box Identication and Fender
Marker Lamps...................................... 538
Roof Marker Lamps................................. 535
Heated Seats................................................ 11
Heater................................................230, 231
Heater......................................................... 235
Highbeam On Light..................................... 263
Highway Hypnosis....................................... 399
Hill and Mountain Roads............................. 400
Hood
Checking Things Under............................ 478
Release................................................... 479
665