Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
29 30A* Passenger power seat
30 10A** A/C clutch relay
31 15A** Power fold mirror relay
32 20A** Fuel pump relay
33 20A** Back-up lamp relay
34 25A** Trailer stop/turn relay
35 5A** ESOF relay coils
36 10A**Gasoline engines:Powertrain
Control Module (PCM) keep alive
power, Canister vent
Diesel engine:Engine Control
Module (ECM) keep alive power
37 10A** Transmission Control Module (TCM)
(Diesel engine only)
38 — Not used
39 50A* ECM power (Diesel engine)
40 30A* Starter relay
41 20A* Power point (Center console -
Front)
42 30A* Trailer park lamp relay
43 20A* Power point (Center console - Rear)
44 30A* Trailer battery charge relay
45 30A* Driver power seat or Memory
module
46 40A* Run/Start relay
47 50A* GPCM #2 (Diesel engine only)
48 30A* ESOF relay hi-lo
49 30A* Wiper motor
50 30A* PCM relay coil, PCM relay (Gasoline
engines only)
51 — Not used
52 — Not used
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Owners Guide (post-2002-fmt)
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Roadside Emergencies
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
53 Relay PCM power bus (Fuses 68, 70, 72,
74, 76) (Diesel engine only)
54 Relay Starter solenoid
55 Relay Trailer tow park lamps
56 Relay Trailer tow battery charge
57 Relay Power Distribution Box (PDB) bus
(fuses 67, 69, 71, 73, 75, 77)
SJB Run /Start bus (Fuses 29–37,
46)
58 Relay ESOF hi-lo
59 Relay PCM power bus (Fuses 68, 70, 72,
74, 76) (Gasoline engines only)
60 Diode Starter relay (Gasoline engines only)
61 Diode A/C clutch
62 Diode Fuel pump
63 15A** Trailer tow back-up lamps
64 5A** Mirror marker lamps
65 — Not used
66 — Not used
67 — Not used
68 — Not used
69 — Not used
70 10A**Gasoline engines:A/C clutch relay
coil, Refrigerant Containment
Switch, Heated PCV
Diesel engine:A/C clutch relay
coil, Clutch switch, Fuel pump
cooler, A/C cycle pressure switch
71 5A** Fuel pump relay diode, PCM/ECM
Run/Start power
72 15A**Gasoline engines:Ignition coils
Diesel engine:Engine TCM
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Observe the following guidelines when handling automotive fuel:
•Extinguish all smoking materials
and any open flames before
refueling your vehicle.
•Always turn off the vehicle before
refueling.
•Automotive fuels can be harmful
or fatal if swallowed. Fuel such as gasoline is highly toxic and if
swallowed can cause death or permanent injury. If fuel is swallowed,
call a physician immediately, even if no symptoms are immediately
apparent. The toxic effects of fuel may not be visible for hours.
•Avoid inhaling fuel vapors. Inhaling too much fuel vapor of any kind
can lead to eye and respiratory tract irritation. In severe cases,
excessive or prolonged breathing of fuel vapor can cause serious
illness and permanent injury.
•Avoid getting fuel liquid in your eyes. If fuel is splashed in the eyes,
remove contact lenses (if worn), flush with water for 15 minutes and
seek medical attention. Failure to seek proper medical attention could
lead to permanent injury.
•Fuels can also be harmful if absorbed through the skin. If fuel is
splashed on the skin and/or clothing, promptly remove contaminated
clothing and wash skin thoroughly with soap and water. Repeated or
prolonged skin contact with fuel liquid or vapor causes skin irritation.
•Be particularly careful if you are taking “Antabuse” or other forms of
disulfiram for the treatment of alcoholism. Breathing gasoline vapors,
or skin contact could cause an adverse reaction. In sensitive
individuals, serious personal injury or sickness may result. If fuel is
splashed on the skin, promptly wash skin thoroughly with soap and
water. Consult a physician immediately if you experience an adverse
reaction.
When refueling always shut the engine off and never allow
sparks or open flames near the filler neck. Never smoke while
refueling. Fuel vapor is extremely hazardous under certain conditions.
Care should be taken to avoid inhaling excess fumes.
The flow of fuel through a fuel pump nozzle can produce static
electricity, which can cause a fire if fuel is pumped into an
ungrounded fuel container.
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Use the following guidelines to avoid static build-up when filling an
ungrounded fuel container:
•Place approved fuel container on the ground.
•DO NOT fill a fuel container while it is in the vehicle (including the
cargo area).
•Keep the fuel pump nozzle in contact with the fuel container while
filling.
•DO NOT use a device that would hold the fuel pump handle in the fill
position.
Refueling
Fuel vapor burns violently and a fuel fire can cause bad injuries.
To help avoid injuries to you and others:
•Read and follow all the instructions on the pump island;
•Turn off your engine when you are refueling;
•Do not smoke if you are near fuel or refueling your vehicle;
•Keep sparks, flames and smoking materials away from fuel;
•Stay outside your vehicle and do not leave the fuel pump unattended
when refueling you vehicle — this is against the law in some places;
•Keep children away from the fuel pump; never let children pump
fuel.
Fuel filler cap
Your fuel tank filler cap has an indexed design with a 1/4 turn on/off
feature.
When fueling your vehicle:
1. Turn the engine off.
2. Carefully turn the filler cap counterclockwise until it stops.
3. Pull to remove the cap from the fuel filler pipe.
4. To install the cap, align the tabs on the cap with the notches on the
filler pipe.
5. Turn the filler cap clockwise until it clicks.
If the “Check Fuel Cap” indicator comes on and stays on after you start
the engine, the fuel filler cap may not be properly installed. Turn off the
engine, remove the fuel filler cap, align the cap properly and reinstall it.
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Octane recommendations
Your vehicle is designed to use
“Regular” unleaded gasoline with
pump (R+M)/2 octane rating of 87.
We do not recommend the use of
gasolines labeled as “Regular” that
are sold with octane ratings of 86 or lower in high altitude areas.
Do not be concerned if your engine sometimes knocks lightly. However, if
it knocks heavily under most driving conditions while you are using fuel
with the recommended octane rating, see your authorized dealer to
prevent any engine damage.
Fuel quality
If you are experiencing starting, rough idle or hesitation driveability
problems, try a different brand of unleaded gasoline. “Premium”
unleaded gasoline is not recommended for vehicles designed to use
“Regular” unleaded gasoline because it may cause these problems to
become more pronounced. If the problems persist, see your authorized
dealer.
Do not add aftermarket fuel additive products to your fuel tank. It
should not be necessary to add any aftermarket products to your fuel
tank if you continue to use high quality fuel of the recommended octane
rating. These products have not been approved for your engine and
could cause damage to the fuel system. Repairs to correct the effects of
using an aftermarket product in your fuel may not be covered by your
warranty.
Many of the world’s automakers approved the World-wide Fuel Charter
that recommends gasoline specifications to provide improved
performance and emission control system protection for your vehicle.
Gasolines that meet the World-wide Fuel Charter should be used when
available. Ask your fuel supplier about gasolines that meet the
World-wide Fuel Charter.
Cleaner air
Ford endorses the use of reformulated “cleaner-burning” gasolines to
improve air quality, per the fuel recommendations in theChoosing the
right fuelsection.
Running out of fuel
Avoid running out of fuel because this situation may have an adverse
affect on powertrain components.
87(R+M)/2 METHOD
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If you have run out of fuel:
•You may need to cycle the ignition from OFF to ON several times after
refueling to allow the fuel system to pump the fuel from the tank to
the engine. On restarting, cranking time will take a few seconds longer
than normal.
•Normally, adding one gallon of fuel is enough to restart the engine. If
the vehicle is out of fuel and on a steep grade, more than one gallon
may be required.
•TheService engine soonindicator (
) may come on. For more
information on theService engine soonindicator, refer to the
Instrument Clusterchapter.
ESSENTIALS OF GOOD FUEL ECONOMY
Measuring techniques
Your best source of information about actual fuel economy is you, the
driver. You must gather information as accurately and consistently as
possible. Fuel expense, frequency of fill-ups or fuel gauge readings are
NOT accurate as a measure of fuel economy. We do not recommend
taking fuel economy measurements during the first 1,000 miles (1,600
km) of driving (engine break-in period). You will get a more accurate
measurement after 2,000 miles-3,000 miles (3,000 km–5,000 km).
Filling the tank
The advertised fuel capacity of the fuel tank on your vehicle is equal to
the rated refill capacity of the fuel tank as listed in theMaintenance
Product Specifications and Capacitiessection of this chapter.
The advertised capacity is the amount of the indicated capacity and the
empty reserve combined. Indicated capacity is the difference in the
amount of fuel in a full tank and a tank when the fuel gauge indicates
empty. Empty reserve is the small amount of fuel remaining in the fuel
tank after the fuel gauge indicates empty.
The amount of usable fuel in the empty reserve varies and should
not be relied upon to increase driving range. When refueling your
vehicle after the fuel gauge indicates empty, you might not be
able to refuel the full amount of the advertised capacity of the
fuel tank due to the empty reserve still present in the tank.
For consistent results when filling the fuel tank:
•Turn the engine/ignition off prior to refueling, an error in the reading
will result if the engine is left running.
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•Use the same filling rate setting (low-medium-high) each time the
tank is filled.
•Allow no more than 2 automatic click-offs when filling.
•Always use fuel with the recommended octane rating.
•Use a known quality gasoline, preferably a national brand.
•Use the same side of the same pump and have the vehicle facing the
same direction each time you fill up.
•Have the vehicle loading and distribution the same every time.
Your results will be most accurate if your filling method is consistent.
Calculating fuel economy
1. Fill the fuel tank completely and record the initial odometer reading
(in miles or kilometers).
2. Each time you fill the tank, record the amount of fuel added (in
gallons or liters).
3. After at least three to five tank fill-ups, fill the fuel tank and record
the current odometer reading.
4. Subtract your initial odometer reading from the current odometer
reading.
5. Follow one of the simple calculations in order to determine fuel
economy:
Calculation 1:Divide total miles traveled by total gallons used.
Calculation 2:Multiply liters used by 100, then divide by total
kilometers traveled.
Keep a record for at least one month and record the type of driving (city
or highway). This will provide an accurate estimate of the vehicle’s fuel
economy under current driving conditions. Additionally, keeping records
during summer and winter will show how temperature impacts fuel
economy. In general, lower temperatures give lower fuel economy.
Driving style - good driving and fuel economy habits
Give consideration to the lists that follow and you may be able to change
a number of variables and improve your fuel economy.
Habits
•Smooth, moderate operation can yield up to 10% savings in fuel.
•Steady speeds without stopping will usually give the best fuel
economy.
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Family entertainment system ....48
Fluid capacities .........................383
Foglamps .....................................85
Four-Wheel Drive vehicles .......276
description ..............................281
driving off road .......................283
electronic shift ................277, 281
indicator light .........................278
lever operated shift ................278
manual locking hubs ..............277
preparing to drive your
vehicle .....................................264
Fuel ............................................362
calculating fuel
economy ..........................130, 367
cap ...........................................364
capacity ...................................383
choosing the right fuel ...........365
comparisons with EPA fuel
economy estimates .................370
detergent in fuel .....................366
filling your vehicle with
fuel ...........................362, 364, 367
filter, specifications ........362, 382
fuel pump shut-off switch .....296
improving fuel economy ........367
octane rating ...................366, 387
quality ......................................366
running out of fuel .................366
safety information relating to
automotive fuels .....................362
Fuel pump shut-off switch .......296
Fuses ..................................297–298
G
Gas cap (see Fuel cap) ............364
Gas mileage
(see Fuel economy) .................367
Gauges .........................................19transmission fluid
temperature gauge ...................23
H
Hazard flashers .........................296
Head restraints .........................162
Headlamps ...................................85
aiming ..................................87, 89
autolamp system .......................85
daytime running lights .............86
flash to pass ..............................86
high beam .................................86
replacing bulbs ...................93–94
turning on and off ....................85
Heating
heating and air conditioning
system ...........................76–77, 80
Homelink wireless control
system ........................................116
Hood ..........................................347
I
Ignition ...............................255, 387
Infant seats
(see Safety seats) .....................196
Inspection/maintenance (I/M)
testing ........................................372
Instrument panel
cleaning ...........................340–341
cluster ........................................12
lighting up panel and interior .87
J
Jump-starting your vehicle ......322
K
Keyless entry system ...............157
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Index
394
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