2003 GMC YUKON DENALI fuel pump

Tow/HauI Mode Light
I
This light is displayed
when the tow/haul mode
has been activated.
For more information, see "Tow/Haul Mode" under
Towing a Trailer on page 4-47.
Fuel Gage
United States
Canada
When the ignition is on, the fuel gage tells you about
how much fuel you have left in your tank.
The gage will first indicate empty before you are out of
fuel, and you should get more fuel as
soon as
possible.
Here are some situations you may experience with your
fuel gage. None of these indicate a problem with the
fuel gage.
At the gas station, the fuel pump shuts off before
the gage reads full.
It takes a little more or less fuel to fill up than the
fuel gage indicated. For example, the gage may
have indicated the tank was half full, but
it actually
took a little more or less than half the tank's
capacity to
fill the tank.
The gage goes back to empty when you turn off the
ignition.
Low Fuel Warning Light
The light next to the fuel gage will come on briefly when
you are starting the engine.
This light comes on when the fuel tank is
low on fuel.
To turn it off, add fuel to the fuel tank. See Fuel on
page 5-5.
3-42

Fuel
Use of the recommended fuel is an important part of the
proper maintenance
of your vehicle.
Gasoline Octane
Use regular unleaded gasoline with a posted octane
of 87 or higher.
If the octane is less than 87, you may
get a heavy knocking noise when you drive. If this
occurs, use a gasoline rated at 87 octane or higher as
soon as possible. Otherwise, you might damage
your engine.
A little pinging noise when you accelerate
or drive uphill
is considered normal. This does not
indicate a problem exists or that a higher-octane fuel is
necessary. If you are using 87 octane or higher-octane
fuel and hear heavy knocking, your engine needs
service.
Gasoline Specifications
It is recommended that gasoline meet specifications
which were developed by the American Automobile
Manufacturers Association and endorsed
by the
Canadian Vehicle Manufacturers Association for better
vehicle performance and engine protection. Gasoline meeting these specifications could provide improved
driveability and emission control system performance
compared to other gasoline.
In Canada, look for the
"Auto Makers' Choice"
label on the pump.
Canada Only
5-5

When you put the fuel cap back on, turn it to the right
(clockwise) until you hear a clicking sound. Make
sure you fully install the cap. The diagnostic system can
determine
if the fuel cap has been left off or improperly
installed. this would allow fuel
to evaporate into the
atmosphere. See Malfunction
indicator Lamp on
page 3-38.
Notice: If you need a new fuel cap, be sure to get
the right type. Your dealer can get one for you.
If you get the wrong type, it may not fit properly.
This may cause your malfunction indicator lamp to
light and may damage your fuel tank and emissions
system. See “Malfunction Indicator Lamp”
in the
Index.
Cillinc a Dortable Fun’ Container
~~ ~
Never fill a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite
the gasoline vapor.
You can
be badly burned and your vehicle
damaged
if this occurs. To help avoid injury to
you and others:
Dispense gasoline only into approved
containers.
@ Do not fill a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed or on any surface other than the ground.
@ Bring the fill nozzle in contact with the
inside of the fill opening before operating
the nozzle. Contact should be maintained until the filling is complete.
Don’t smoke while pumping gasoline.
5-9

Fuses
RR HVAC
Usage
Rear Climate Control
AUX PWR I
Auxiliary Power
Outlet
- Console
IGN
1
PCM 1 Ignition Relay
Electronic Throttle Control,
ETC/ECM Powertrain Control Module
Electronic Brake Controller
IGN E Instrument Panel Cluster,
Air
Conditioning Relay, Turn
SignaVHazard Switch, Starter
Relav
RTD I Ride Control I
TRL B/U
~~
I Backup LampsTrailG Wiring 1
PCM B I
Powertrain Control Module,
Fuel Pumr,
I I
F/PMP I Fuel Pump (Relay)
B/U LP
I
Back-up Lamps, Automatic
Transmission Shift Lock
I
Control System
RR DEFOG
Rear Window Defoaaer
HDLP-HI
~~~ ____
HeadlampHighBeam Relay
PRIME Not Used
Fuses I Usage I
SIR Supplemental Inflatable
Restraint System
FRT PARK
DRL Front Parking Lamps,
Sidemarker Lamps
Daytime Running Lamps
(Relav)
SEO IGN
Truck Body Controller Ignition
TBC IGN1 Rear
Defog Relay
HI HDLP-LT High
Beam Headlamp-Left
LH HID Not
Used
DRL
I Davtime Runnina LamDs I
Instrument Panel
IPC/DIC Cluster/Driver Information
HI HDLP-RT
HDLP-LOW High
Beam Headlamp-Right
Headlamp Low Beam Relav
A/C COMP
I Air Conditionina Comm-essor I v
A/C COMP Air
Conditioning Compressor
Relav
5-94