2003 FORD F750 heater

Fuse/Relay
LocationFuse Amp
RatingPassenger Compartment Fuse
Panel Description
29 10A Cluster, GEM, 7.3L Power Stroke
PCM (clutch switch input), APCM
(7.3L Power Stroke only),
Overhead console (SuperCrewzer
only), Keyless entry module
(SuperCrewzer only), Traxx
(Fuel) module (SuperCrewzer
only)
30 30A 7.3L Power Stroke PCM diode,
7.3L Power Stroke fuel heater
31 15A Allison MD Transmission, Neutral
start relay and PCM (7.3L Power
Stroke only)
Relay 1—Interior lamps
Relay 2—Not used
Relay 3—Horn
Relay 4—One touch down power window
Relay 5—Not used
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.
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.
Roadside Emergencies
155

The high-current fuses and relays are coded as follows.
Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
1 15A* Park lamps, Roof lamps
2 25A* Cummins Powertrain Control
Module (PCM)
15A* Foglamps (SuperCrewzer only)
3 10A* Generator
4 15A* Washer pump
5 15A* CAT air intake heater relay,
Cummins PCM
6 20A* CAT PCM, Cummins PCM
7 15A* Stop lamps
8 25A* CAT fuel heater
9 30A* Trailer hook-up lamps
(SuperCrewzer only)
10 15A* Shift modulator (Allison AT
transmission only) (except for
F–650 SuperCrewzer and
Caterpillar/Cummins)
503
304
303
302301
502
501
207201
202
203
204122118114110106102
121117113109105101
120116112108104
119115111107103
24
209206
208
18161412108642
1715131197531
205
23
22
21
401
20
19
Roadside Emergencies
156

Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
11 20A* Allison MD transmission, Allison
2000/2400 transmission
12 10A* Keyless entry module
(SuperCrewzer only)
13 10A* Park brake adjustment module
(SuperCrewzer only)
14—Not used
15 7.5A* Body builder prep (hydraulic
brake vehicles only)
16 10A* Allison 2000/2400 transmission
(except F650 SuperCrewzer)
17 5A* Radio (SuperCrewzer only)
18—Not used
19—Not used
20—Not used
21 10A* GEM (hydraulic brake vehicles
only)
22—Not used
23—Not used
24—Not used
101 40A** Anti-lock Brake System (ABS)
(air brake vehicles only)
102 20A** Body builder prep run feed
103 50A** Ignition switch (Junction box
fuses 8, 9, 11, 19, 20, 22, 23, 24,
25, 29, 30, 31)
104 20A** Power point
105 20A** Power door locks
106 30A** Headlamps
107 50A** Junction box battery feed (fuses
1, 2, 3, 4, 12, 13, 14, 15)
108 40A** Cummins fuel heater
Roadside Emergencies
157

Fuse/Relay
LocationFuse Amp
RatingPower Distribution Box
Description
301—Fuel heater relay (CAT and
Cummins only)/7.3L Power Stroke
PCM relay)
302—Park lamps relay
303—Blower motor relay
304—Air ABS relay
401—Not used
501—Not used
502—Not used
503 Diode 7.3L Power Stroke PCM diode
* Mini Fuses ** Maxi Fuses
Relays
The relay box is located on the rear crossmember.
Air Brake Trailer Tow Relays (if equipped)
Roadside Emergencies
159

JUMP STARTING YOUR VEHICLE
The gases around the battery can explode if exposed to flames,
sparks, or lit cigarettes. An explosion could result in injury or
vehicle damage.
Batteries contain sulfuric acid which burns skin, eyes, and
clothing.
Preparing your vehicle
Also see the label on the battery.
1. Use only a 12–volt supply to start your vehicle. If you connect your
battery to a 24–volt power supply you can damage your starter, ignition
system and other electrical components. Do not attach the jumper cables
to the glow plug relay as this could severely damage the glow plugs,
injector driver module and PCM.
2. Do not disconnect the battery of the disabled vehicle as this could
damage the vehicle’s electrical system.
3. Park the booster vehicle close to the disabled vehicle making sure
theydo nottouch. Set the parking brake on both vehicles and stay clear
of the engine cooling fan and other moving parts.
4. Check all battery terminals and remove any excessive corrosion before
you attach the battery cables. Ensure the vent caps are tight and level.
5. Turn the heater fan on in both vehicles to protect any electrical
surges. Turn all other accessories off.
Roadside Emergencies
162

D
Daytime running lamps
(see Lamps) ................................61
Driving under special
conditions
through water .........................148
E
Emergencies, roadside
jump-starting ..........................165
Emission control system ..........226
Engine
check engine/service engine
soon light ....................................9
cleaning ...................................175
coolant .....................................186
Engine block heater .................110
Engine fan .................................192
Engine oil ..................................180
checking and adding ..............180
oil pressure gauge ....................17
recommendations ...................181
Exhaust fumes ..........................112
F
Foglamps .....................................62
Fuel ............................................192
calculating fuel
economy ..........................198, 200
choosing the right fuel ...........193
filling your vehicle
with fuel ..................................192
filter, specifications ........194–196
gauge .........................................18
improving fuel
economy ..........................198, 200safety information relating
to automotive fuels ................192
Fuses ..................................151–152
G
Gas mileage
(see Fuel economy) .........198, 200
Gauges .........................................15
battery voltage gauge ...............17
engine coolant temperature
gauge .........................................16
engine oil pressure gauge ........16
fuel gauge ..................................18
odometer ...................................18
speedometer .............................18
tachometer ................................19
trip odometer ............................19
H
Hazard flashers .........................150
Headlamps ...................................61
aiming ........................................62
daytime running lights .............61
flash to pass ..............................61
high beam ...........................14, 61
turning on and off ....................61
warning chime ..........................15
Heating
heater only system ...................56
heating and air conditioning
system .......................................57
I
Ignition
removing the key ....................145
Infant seats
(see Safety seats) .....................104
Index
244