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Power distribution box
The power distribution box is located in the engine compartment. The
power distribution box contains high-current fuses that protect your
vehicle’s main electrical systems from overloads.
Always disconnect the battery before servicing high current
fuses.
To reduce risk of electrical shock, always replace the cover to
the Power Distribution Box before reconnecting the battery or
refilling fluid reservoirs.
If the battery has been disconnected and reconnected, refer to the
Batterysection of theMaintenance and Specificationschapter.
The high-current fuses are coded as follows:
Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
1 Relay Blower motor/Variable blower
control (Dual Zone Climate Control)
2 Relay Electronic Shift-on-the-Fly (ESOF)
Lo-Hi
3 Relay Heater mirror
4 — Not used
5 30A* Trailer Brake Controller (TBC)
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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
6 40A* ABS module (Pump)
7 30A* Upfitter auxiliary switch #1
8 30A* Upfitter auxiliary switch #2
9 40A* ABS module (Coil)
10 20A* Cigar lighter
11 20A* Instrument panel power point
12 15A** Brake On/Off (BOO) relay feed
13 5A ** Brake switch, Brake switch relay
coil, SJB module, 4x4 module
14 — Not used
15 — Not used
16 Relay A/C clutch
17 Relay Not used
18 Relay Fuel Pump Driver Module (FPDM),
Fuel injectors (Gasoline engines),
Diesel Fuel Control Module (DFCM)
(Diesel engine)
19 Relay Back-up lamps, Reverse Sensing
System (RSS), Engine compartment
fuse 63
20 Relay Trailer stop/turn (Left)
21 Relay Trailer stop/turn (Right)
22 Relay Stop lamps, Center High-Mounted
Stop Lamp (CHMSL), TBC,
Customer access
23 15A** Heater mirror
24 40A* Blower motor relay
25 — Not used
26 30A* ESOF relay lo-hi
27 50A* Glow Plug Control Module (GPCM)
#1 (Diesel engine only)
28 20A* Heated mirror relay
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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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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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Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
73 2A** Reverse Camera System (RCS)
74 20A**Gasoline engines:VPWR: HEGO,
CMS, MAFS, EVMV, CMCV, VCT,
IMTV
Diesel engine:VPWR: Engine loads
75 5A** Back-up relay coil power
76 20A**Gasoline engines:VPWR: PCM
Diesel engine:VPWR: ECM
77 10A** ABS module logic
* Cartridge fuses ** Mini fuses
CHANGING A FLAT TIRE
If you get a flat tire while driving:
•do not brake heavily.
•gradually decrease the vehicle’s speed.
•hold the steering wheel firmly.
•slowly move to a safe place on the side of the road.
Your vehicle may be equipped with a conventional spare tire that is
different in one or more of the following: type, brand, size, speed rating
and tread design. If this is the case, this dissimilar spare tire is still rated
for your vehicle loads (GAWR and GVWR).Temporary spare tires are not
equipped with Tire Pressure Monitor System (TPMS) sensors if the
system is present.
The use of tire sealant may damage your Tire Pressure
Monitoring System (if equipped) and should not be used.
If your vehicle is equipped with a Tire Pressure Monitoring
System, refer toTire Pressure Monitoring Systemin theTires,
Wheels and Loadingchapter for more information. If the tire pressure
monitor sensor becomes damaged, it will no longer function.
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Rear seat entertainment
system ..........................................48
Rear video camera ....................274
Relays ........................................297
Remote entry system ...............151
illuminated entry ............155–156
locking/unlocking
doors ........................146, 151–152
Reverse sensing system ...........272
Roadside assistance ..................294
S
Safety Belt Maintenance ..........183
Safety belts (see Safety
restraints) ..........170, 172–174, 176
Safety defects, reporting ..335–336
Safety
restraints ...........170, 172–174, 176
Belt-Minder...........................179
extension assembly ................183
for adults .................172–174, 176
for children .....................192–193
lap belt ....................................178
safety belt maintenance .........183
warning light and
chime ...............................178–179
Safety seats for children ..........196
Safety Compliance
Certification Label ....................388
Satellite Radio Information ........44
Seat belts
(see Safety restraints) .............170
Seats ..........................................162
child safety seats ....................196
cleaning ...................................343
heated ........................................80
memory seat ...................152, 168SecuriLock passive anti-theft
system ................................159–160
Servicing your vehicle ..............346
Setting the clock
AM/FM/CD .................................28
AM/FM/In-dash 6 CD ................34
Snowplowing .................8, 291–293
Spark plugs,
specifications .....................382, 387
Special notice ................................9
ambulance conversions ..............8
diesel-powered vehicles .............8
utility-type vehicles ....................8
Speed control ............................109
Starting your vehicle ........255–257
jump starting ..........................322
Steering wheel
controls ....................................112
tilting .........................................99
T
Tailgate ......................................140
Tilt steering wheel ......................99
Tire Pressure Monitoring
System (TPMS)
Tires, Wheels and Loading ....224
Tires ...................................206–208
alignment ................................216
care ..........................................212
changing ..........................310, 312
checking the pressure ............211
inflating ...................................209
label .........................................223
replacing ..................................214
rotating ....................................217
safety practices .......................215
sidewall information ...............219
2008 F-250/350/450/550(f23)
Owners Guide (post-2002-fmt)
USA(fus)
Index
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