Fuse/Relay
LocationFuse Amp
RatingProtected Circuits
31 5A Trailer brake controller (brake
signal), Customer access
32 15A Moon roof, Auto dimming mirrors,
Power invertor, Driver and
passenger door lock switch
illumination
33 10A Restraint control module
34 10A Not used (spare)
35 5A Select shift switch, Reverse park
aid module, Trailer brake control
module
36 10A Fuel tank select switch
37 10A PTC heater
38 10A Radio faceplate
39 15A High beam headlamps
40 10A Parking lamps (in mirrors), Roof
marker lamps
41 7.5A Passenger airbag deactivation
indicator
42 5A Not used (spare)
43 10A Wiper relay
44 10A Upfitter switches
45 5A Not used (spare)
46 10A Climate control
47 15A Fog lamps, Fog lamp indicator (in
switch)
48 30A Circuit
BreakerPower windows switch, Power
rear sliding window switch
49 Relay Delayed accessory
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.
Roadside Emergencies
329
2012 F-250/350/450/550(f23)
Owners Guide, 1st Printing
USA(fus)
WARNING:Always disconnect the battery before servicing high
current fuses.
WARNING: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
RatingProtected Circuits
1 Relay Blower motor
2 — Not used
3 Relay Urea heaters (diesel engine)
4 — Not used
5 Relay Rear window defroster
6 — Not used
7 50A* Rear window defroster
8 30A* Passenger seat
9 30A* Driver seat
10 — Not used
11 — Not used
12 30A* Driver smart window
13 — Not used
Roadside Emergencies
330
2012 F-250/350/450/550(f23)
Owners Guide, 1st Printing
USA(fus)