fuse GMC YUKON 2000 User Guide

4-64
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
A jumper harness for an electric trailer brake controller
and a trailer battery feed fuse are included with this
trailering package. (See ªInstrument Panel Jumper
Wiring Harnessº later in this section.)
If you need to tow a light
-duty trailer with a standard
four
-way round pin connector, an adapter connector is
available from your dealer.Instrument Panel Jumper Wiring Harness
This harness is included with the heavy-duty trailer
wiring package. The harness is for an electric trailer
brake controller and includes a trailer battery feed fuse.
This harness and fuse should be installed by your dealer
or a qualified service center.

6-3
CAUTION:
You can be injured and your vehicle could be
damaged if you try to do service work on a
vehicle without knowing enough about it.

Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.

Be sure to use the proper nuts, bolts and
other fasteners. ªEnglishº and ªmetricº
fasteners can be easily confused. If you use
the wrong fasteners, parts can later break
or fall off. You could be hurt.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around it. This may cause wind noise
and affect windshield washer performance. Check with
your dealer before adding equipment to the outside of
your vehicle.
Fuel
Use regular unleaded gasoline rated at 87 octane or
higher. It is recommended that the gasoline meet
specifications which have been developed by the
American Automobile Manufacturers Association
(AAMA) and endorsed by the Canadian Motor
Vehicle Manufacturers Association for better vehicle
performance and engine protection. Gasolines meeting
the AAMA specification could provide improved
driveability and emission control system performance
compared to other gasolines.
Be sure the posted octane is at least 87. If the octane is
less than 87, you may get a heavy knocking noise when
you drive. If it's bad enough, it can damage your engine.
If you're using fuel rated at 87 octane or higher and
you hear heavy knocking, your engine needs service.
But don't worry if you hear a little pinging noise when
you're accelerating or driving up a hill. That's normal,
and you don't have to buy a higher octane fuel to get
rid of pinging. It's the heavy, constant knock that means
you have a problem.

6-55
Electrical System
Add-On Electrical Equipment
NOTICE:
Don't add anything electrical to your vehicle
unless you check with your dealer first. Some
electrical equipment can damage your vehicle
and the damage wouldn't be covered by your
warranty. Some add
-on electrical equipment
can keep other components from working as
they should.
Your vehicle has an air bag system. Before attempting to
add anything electrical to your vehicle, see ªServicing
Your Air Bag
-Equipped Vehicleº in the Index.
Windshield Wipers
The windshield wiper motor is protected by an internal
circuit breaker and a fuse. If the motor overheats due to
heavy snow, etc., the wiper will stop until the motor
cools. If the overload is caused by some electrical
problem and not snow, etc., be sure to get it fixed.
Power Windows and Other Power Options
Circuit breakers protect the power windows and other
power accessories. When the current load is too heavy,
the circuit breaker opens and closes, protecting the
circuit until the problem is fixed or goes away.
Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses, circuit breakers
and fusible thermal links. This greatly reduces the
chance of fires caused by electrical problems.
Look at the silver
-colored band inside the fuse. If the
band is broken or melted, replace the fuse. Be sure you
replace a bad fuse with a new one of the identical size
and rating.

6-56
If you ever have a problem on the road and don't have
a spare fuse, you can borrow one that has the same
amperage. Just pick some feature of your vehicle that
you can get along without
-- like the radio or cigarette
lighter
-- and use its fuse, if it is the correct amperage.
Replace it as soon as you can.
Instrument Panel Fuse Block
The fuse block access door
is on the driver's side edge
of the instrument panel.
Pull off the cover to access
the fuse block.
You can remove fuses with a fuse extractor which is
mounted to the fuse block access door. To remove fuses
if you don't have a fuse extractor, hold the end of the
fuse between your thumb and index finger and pull
straight out.You may have spare fuses located behind the fuse block
access door. These can be used to replace a bad fuse.
However, make sure it is of the correct amperage.
NAME Usage
L BODY Retained Accessory Power Relay
LOCK Power Door Locks
DRV UNLOCK Power Door Lock Relay

6-59
Underhood Electrical CenterThe underhood electrical center is located on the
driver's side of the engine compartment near the
battery. Lift the cover for access to the fuse/relay block.
You can remove fuses with a fuse extractor. The fuse
extractor is located in the underhood electrical center.
To remove fuses if you don't have a fuse extractor,
hold the end of the fuse between your thumb and index
finger and pull straight out.