What Fuel to Use
In the United States, for best results use No. 2-D diesel
fuel year-round (above and below freezing conditions)
as oil companies blend No. 2-D fuel to address climate
differences. No. 1-D diesel fuel may be used in very
cold temperatures (when it stays below 0°F or−18°C);
however, it will produce a power and fuel economy
loss. Avoid the use of No. 1-D diesel fuel in warm or hot
climates. It may result in stalling, poor starting when
the engine is hot, and may damage the fuel injection
system.
At a minimum, the diesel fuel you use should meet the
latest version of ASTM specification D 975 (Grade
Low Sulfur) in the United States. In addition, the Engine
Manufacturers Association (EMA) has identified
properties of an improved diesel fuel for better engine
performance and durability. Diesel fuels corresponding
to the EMA Recommended Guideline on Premium
Diesel Fuel (FQP-1A) could provide better starting, less
noise, and better vehicle performance. If there are
questions about the fuel you are using, contact your fuel
supplier.
If your vehicle has the 6.6L engine, it is acceptable to
use diesel fuel containing up to 5% biodiesel (B5),
but the final blended fuel must meet the same
specification, ASTM D 975 (Grade Low Sulfur), as other
fuels used in your vehicle, and the biodiesel used for
making this fuel must meet the latest version ofASTM specification D 6751. Biodiesel is produced from
vegetable oils or animal fat that have been chemically
modified to reduce the possibility of damage to your fuel
system and engine. Higher concentration (i.e., greater
than B5) biodiesel-containing fuels or the use of
unmodified bio-oils blended into diesel fuel at any
concentration is not recommended and could damage
your fuel system and engine. Such damage would
not be covered by your warranty. If there are questions
about the biodiesel-containing fuels you are using,
contact your fuel supplier.
Diesel fuel may foam when you fill your tank. This can
cause the automatic pump nozzle to shut off, even
though your tank is not full. If this happens, just
wait for the foaming to stop and then continue to fill
your tank.
{CAUTION:
Heat coming from the engine may cause the
fuel to expand and force the fuel out of your
tank. If something ignites the fuel, a re could
start and people could be burned. To help
avoid this, ll your fuel tank only until the
automatic nozzle shuts off. Do not try to top
it off.
5-8
Headlamp Wiring
The headlamp wiring is protected by a circuit breaker in
the light switch. An electrical overload will cause the
lights to go on and off, or in some cases to remain off. If
this happens, have your headlamp wiring checked
right away.
Windshield Wiper Fuses
The windshield wiper motor is protected by a circuit
breaker inside the motor and a circuit breaker or fuse in
the fuse block. If the motor overheats, the wipers will
stop until the motor cools. If the overload is caused by
an electrical problem, be sure to get it fixed.
Fusible Links
A fusible link is a short piece of wire several gauge
sizes smaller than the circuit it protects. It will melt in an
overload situation, opening the circuit.
Your starter and other circuits have these fusible links.
The size is printed on the insulation. If the insulation
is burned beyond recognition, consult your GM dealer
for the proper size. Replace a fusible link with one of the
same size and insulation type. Fusible link insulation
is a special purpose high-temperature material.The hydraulic brake booster motor feed circuit and
starter circuit are protected by a fusible link. Vehicles
with a diesel engine have a fusible link for the intake
heater feed circuit.
Power Windows and Other
Power Options
Circuit breakers in the fuse panel protect the power
windows and other power accessories. When the current
load is too heavy, the circuit breaker opens. This
protects the circuit until the current load returns to
normal or the problem is fixed.
Fuses and Circuit Breakers
The wiring circuits in your vehicle are protected from
short circuits by a combination of fuses, circuit breakers,
maxi-fuses and fusible links. This greatly reduces the
chance of a fire caused by an electrical problem. There
may be a fuse taped to the wiring harness near the
hydraulic brake booster.
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Circuit Breaker Usage
9 Courtesy Lamps
10Warning Lights, Gages and
Indicators
11 Starter
12 Rear Axle/Four-Wheel-Drive
13Trailer Turn Signals/Hazard
Warning Flashers
14 Radio/Chime
15 Daytime Running Lamps
16 Airbag System
17 Exterior/Interior Lamps
18 Parking Brake
19 Accessory Power
20 Ignition 4
21 Sidemarker Lamps
22 Turn Signal/Backup Lamps
23 Transmission
24 Hydraulics/Air Brake
A Spare
B SpareFuse Usage
HTD/MIRR Heated Mirrors
Blank Not Used
RT TRN TRLR Passenger’s Side Trailer Turn Signal
Blank Not Used
LT TRN TRLR Driver’s Side Trailer Turn Signal
Blank Not Used
BRK Brake Warning Lamp
RT PRK Passenger’s Side Parking Lamps
Blank Not Used
Blank Not Used
Blank Not Used
LT PARK Driver’s Side Parking Lamps
Blank Not Used
RT REAR
TRN/STOPPassenger’s Side Rear Turn
Signal/Stoplamp
LT REAR
TRN/STOPDriver’s Side Rear Turn
Signal/Stoplamp
RADIO Radio
Blank Not Used
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