2012 Ford F-150 Fuse Box Diagram: Full Fuse and Relay Charts
Your 2012 F-150 has two fuse boxes. The Smart Junction Box (cab panel) sits behind the passenger side kick panel, right of the steering wheel. The power distribution box is in the engine compartment, center, above the radiator. The cigar lighter is fuse 22, rated 20A, in the engine bay box, not the cab panel.
Where are the fuse boxes on a 2012 F-150?
Smart Junction Box (passenger compartment panel). Behind the passenger side kick panel, right of the steering wheel, behind a removable cover. This holds fuses 1 to 48 plus one relay position, all mini fuses except the circuit breaker at 48.
Power distribution box. Engine compartment, center, above the radiator, sometimes called the Battery Junction Box. It carries 85 numbered positions split between mini fuses, cartridge (FMX/JCase) fuses, and dedicated relays, plus an auxiliary relay box on SVT Raptor trucks near the windshield.
Most sites get this wrong: fuse 41 changed between the 2011 and 2012 F-150
The 2009 to 2014 F-150 is one truck generation, so most fuse charts online publish a single merged table for all six years. That merge hides a real change that lands right on 2012.
I cross-checked fuse-box.info’s separate year tables for 2009 through 2014 against StartMyCar’s 2012-specific page. Both agree exactly: fuse 41 in the power distribution box is not used on 2009 through 2011 trucks. Starting with the 2012 model year, fuse 41 carries a live 15A mini fuse for the front camera washer on SVT Raptor trucks. Both sources also add a fifth position, front camera washer relay, to the auxiliary relay box that did not exist in 2011.
A separate fuse index published under a “2012” URL lists fuse 41 as not used and fuse 35 as a left HID headlamp circuit instead. That page’s own introduction says it is showing “the 2011 F150 fuse box diagrams,” and the HID headlamp assignment it lists actually belongs to the 2013 to 2014 F-150, confirmed against this site’s own cross-checked 2013 article. Where a page disagrees with two sources that agree with each other and are dated to the correct year, trust the two that match.
| What changed | 2009 to 2011 | 2012 to 2014 |
|---|---|---|
| Fuse 41, power distribution box | Not used | Front camera washer (SVT Raptor), 15A |
| Auxiliary relay box, position 5 | Not used | Front camera washer relay |
| Fuse 16, power distribution box | Not used | Not used (unchanged, HID headlamp starts 2013) |
| Fuse 22, power distribution box | Cigar lighter, 20A | Unchanged, 20A |
2012 F-150 Smart Junction Box fuse chart
Passenger side kick panel. All mini fuses except the circuit breaker at position 48. Unchanged from 2011, and carries through 2014.
| Fuse | Amps | Circuit protected |
|---|---|---|
| 1 | 30A | Driver side front window |
| 2 | 15A | SYNC |
| 3 | 30A | Passenger side front window |
| 4 | 10A | Interior lamps |
| 5 | 20A | Memory module |
| 6 | 5A | Not used (spare) |
| 7 | 7.5A | Power mirror switch, memory seat module |
| 8 | 10A | Not used (spare) |
| 9 | 10A | Radio display, GPS module, navigation display |
| 10 | 10A | Run/accessory relay |
| 11 | 10A | Instrument cluster |
| 12 | 15A | Interior lighting, puddle lamps, backlighting, cargo lamp |
| 13 | 15A | Right turn signals, stop lamps |
| 14 | 15A | Left turn signals, stop lamps |
| 15 | 15A | Reverse lights, high mounted stop lamp |
| 16 | 10A | Right low beam headlamp |
| 17 | 10A | Left low beam headlamp |
| 18 | 10A | Brake shift interlock, keypad illumination, PCM wakeup, PATS |
| 19 | 20A | Audio amplifier |
| 20 | 20A | Power door locks |
| 21 | 10A | Ambient lighting |
| 22 | 20A | Horn |
| 23 | 15A | Steering wheel control module |
| 24 | 15A | Datalink connector, steering wheel control module |
| 25 | 15A | Not used (spare) |
| 26 | 5A | Radio frequency module |
| 27 | 20A | Not used (spare) |
| 28 | 15A | Ignition switch |
| 29 | 20A | Radio, navigation |
| 30 | 15A | Front parking lamps |
| 31 | 5A | Brake on/off, IP and engine |
| 32 | 15A | Delay/accessory: moon roof, power windows, locks, auto dimming mirror, compass |
| 33 | 10A | Heated seats |
| 34 | 10A | Reverse sensing system, 4×4 switch, rear video, off road indicator (SVT Raptor) |
| 35 | 5A | Hill descent switch (SVT Raptor) |
| 36 | 10A | Restraint control module, occupant classification system module |
| 37 | 10A | Trailer brake control |
| 38 | 10A | Delayed accessory: 110V power point, radio (AM/FM) |
| 39 | 15A | High beam headlamps |
| 40 | 10A | Rear park lamps |
| 41 | 7.5A | Passenger airbag deactivation indicator, upfitter switch (SVT Raptor) |
| 42 | 5A | Overdrive cancel switch |
| 43 | 10A | Not used (spare) |
| 44 | 10A | Not used (spare) |
| 45 | 5A | Not used (spare) |
| 46 | 10A | Climate controls module |
| 47 | 15A | Fog lamps, exterior mirror turn signals |
| 48 | 30A Circuit Breaker | Power rear windows, power sliding back window |
Relay in this panel: position 49, delayed accessory relay. Assignments vary with trim and options. Your truck may not use every position listed.
2012 F-150 power distribution box fuse chart
Engine compartment, center, above the radiator. Full fuse and relay assignment, with the 2012-specific fuse 41 change noted.
| Position | Amps | Circuit protected |
|---|---|---|
| 1 | Relay | PCM relay (3.7L, 5.0L, 6.2L engines) |
| 2 | Relay | Starter relay |
| 3 | Relay | Blower motor relay |
| 4 | Relay | Rear window defroster relay |
| 5 | Relay | Electric fan relay (high speed) |
| 6 | Relay | Trailer tow park lamp relay |
| 7 | Relay | Run/start relay |
| 8 | Relay | Fuel pump relay |
| 9 | Relay | Trailer tow battery charger relay |
| 10 | Relay | PCM relay (3.5L engine) |
| 11 | 30A | Power running board motors |
| 12 | 40A / 50A | Electric fan (50A on 6.2L with max trailer tow, SVT Raptor) |
| 13 | 30A | Starter relay power |
| 14 | 30A | Passenger power seat |
| 15 | 40A / 50A | Electric fan (50A on 6.2L with max trailer tow, SVT Raptor) |
| 16 | – | Not used |
| 17 | 30A | Trailer brake control |
| 18 | 30A | Upfitter switch 1 (SVT Raptor) |
| 19 | 30A | Upfitter switch 2 (SVT Raptor) |
| 20 | 20A | 4×4 module, electronic shift |
| 21 | 30A | Trailer tow battery charge relay power |
| 22 | 20A | Cigar lighter |
| 23 | Relay | A/C clutch relay |
| 24 | – | Not used |
| 25 | Relay | Vacuum pump relay (3.5L engine) |
| 26 | 10A | PCM keep alive power, PCM relay coil, canister vent solenoid (3.7L, 5.0L, 6.2L) |
| 27 | 20A | Fuel pump relay power |
| 28 | 10A | Upfitter switch 4 (SVT Raptor) |
| 29 | 10A | 4×4 IWE solenoid |
| 30 | 10A | A/C clutch |
| 31 | 15A | Run/start relay power |
| 32 | 40A | Rear window defroster relay power, heated mirror relay power |
| 33 | 40A | 110V AC power point |
| 34 | 40A / 50A | PCM relay power (50A on 3.5L engine) |
| 35 | – | Not used |
| 36 | 30A | Roll stability control / anti-lock brake system |
| 37 | Relay | Trailer tow left stop/turn relay |
| 38 | Relay | Trailer tow right stop/turn relay |
| 39 | Relay | Trailer tow back-up lamps relay |
| 40 | Relay | Electric fan relay |
| 41 | 15A | Front camera washer (SVT Raptor). Not used on 2009-2011 trucks, live starting 2012. |
| 42 | 5A | Run/start coil |
| 43 | 15A | Trailer tow back-up lamp relay power |
| 44 | 15A | Upfitter switch 3 (SVT Raptor) |
| 45 | 10A | Alternator sensor, non-6.2L engines |
| 46 | 10A | Brake on/off (BOO) switch |
| 47 | 60A | Roll stability control / anti-lock brake system module |
| 48 | 20A | Moon roof |
| 49 | 30A | Wipers |
| 50 | – | Not used |
| 51 | 40A | Blower motor relay power |
| 52 | 5A | Run/start: electronic power assist steering, blower relay coil |
| 53 | 5A | Run/start: PCM |
| 54 | 5A | Run/start: 4×4 module, back-up lamps, RSC/ABS, trailer tow battery charge relay coil, rear window defroster relay coil, front camera washer relay coil (SVT Raptor) |
| 55 | – | Not used |
| 56 | 15A | Heated mirrors |
| 57 | – | Not used |
| 58 | – | Not used |
| 59 | – | Not used |
| 60 | – | Not used |
| 61 | – | Not used |
| 62 | Relay | Wiper motor relay |
| 63 | 25A | Electric fan |
| 64 | 40A | Vacuum pump relay power (3.5L engine) |
| 65 | 20A | Auxiliary power point, instrument panel |
| 66 | 20A | Auxiliary power point, inside center console |
| 67 | 20A | Trailer tow park lamps relay power |
| 68 | 25A | 4×4 module |
| 69 | 30A | Passenger heated/cooled seats |
| 70 | – | Not used |
| 71 | 20A | Heated rear seats |
| 72 | 20A | Auxiliary power point, rear |
| 73 | 20A | Trailer tow stop/turn lamps relay power |
| 74 | 30A | Driver power seat, memory module |
| 75 | 15A / 25A | PCM voltage power 1 (25A on 3.5L engine) |
| 76 | 20A | PCM voltage power 2: general powertrain, MAF/IAT sensor (3.7L, 5.0L, 6.2L) or canister vent solenoid (3.5L) |
| 77 | 10A | PCM voltage power 3: emission related components, electric fan relay coil |
| 78 | 15A / 20A | PCM voltage power 4, ignition coils (20A on 6.2L engine) |
| 79 | 5A | Rain sensor |
| 80 | – | Not used |
| 81 | – | Not used |
| 82 | – | Not used |
| 83 | – | Not used |
| 84 | – | Not used |
| 85 | Relay | Electric fan relay (low speed) |
Auxiliary relay box (SVT Raptor only), near the windshield: position 1 upfitter relay 1, position 2 upfitter relay 2, position 3 upfitter relay 3, position 4 upfitter relay 4, position 5 front camera washer relay (new for 2012), position 6 not used.
What if a fuse keeps blowing on your 2012 F-150?
A fuse that blows once is usually a fluke. A fuse that blows again within a week means the fault is upstream, not in the fuse itself.
| Symptom | Check this fuse |
|---|---|
| Cigar lighter or front power point dead | Fuse 22, power distribution box, 20A |
| Console or rear power point dead | Fuse 66 (console) or fuse 72 (rear), power distribution box, 20A each |
| Horn does not sound | Fuse 22, Smart Junction Box, 20A |
| Blower motor does not run on any speed | Fuse 51, power distribution box, 40A, plus relay position 3 |
| One low beam headlamp out, bulb tests good | Fuse 16 (right) or fuse 17 (left), Smart Junction Box, 10A |
| Radio or navigation screen dead | Fuse 29, Smart Junction Box, 20A |
| Power windows on the doors do not move | Fuse 1 (driver) or fuse 3 (passenger), Smart Junction Box, 30A each |
| Rear or sliding back window will not move | Circuit breaker, fuse 48, Smart Junction Box, 30A |
| SVT Raptor front camera washer does not fire | Fuse 41, power distribution box, 15A. Not present on 2009-2011 trucks. |
| 4×4 will not shift electronically | Fuse 20, power distribution box, 20A |
If the replacement fuse blows again immediately, stop replacing fuses and check for a short. A cheap fuse assortment kit covers every rating on this truck and costs less than a single dealer visit. Any brand meeting the ATO/ATC mini fuse standard fits. Fuse assortment kits on Amazon.
Where is the cigar lighter fuse on a 2012 F-150?
Fuse 22 in the power distribution box, rated 20A. That box is in the engine compartment, center, above the radiator, not the cab panel. A second fuse 22 exists in the Smart Junction Box for the horn, at 20A, which is a common mix-up if you only check one box.
Is the 2012 F-150 fuse layout the same as 2011?
Almost entirely, with one exception. The Smart Junction Box table is identical. The power distribution box is identical except fuse 41, which goes from not used in 2011 to a live 15A circuit for the SVT Raptor front camera washer in 2012. If your truck is a 2013 or 2014 model instead, do not use this chart for fuses 16, 21 and 35. Ford adds an HID headlamp circuit at fuse 16 and 35, and retires ambient lighting from fuse 21, starting with the 2013 model year.
If the fuse keeps blowing after a fresh fuse, what next?
A fuse protects the wire, not the part. A short to ground or a chafed harness will blow a fresh fuse in seconds. At that point you need to read live data rather than keep replacing fuses, which means a scan tool. Our Ford diagnostic tool comparison covers what actually works on these trucks, and our OBD2 scanner picks for the F-150 cover the budget end. A basic multimeter set to ohms will confirm a short before you spend on a scan tool.
2012 F-150 fuse box quick reference
| Circuit | Fuse | Box | Amps |
|---|---|---|---|
| Cigar lighter / front power point | 22 | Power distribution | 20A |
| Horn | 22 | Smart Junction Box | 20A |
| Blower motor | 51 | Power distribution | 40A |
| Radio / navigation | 29 | Smart Junction Box | 20A |
| Right / left low beam | 16 / 17 | Smart Junction Box | 10A each |
| Rear window / sliding back window | 48 (breaker) | Smart Junction Box | 30A |
| Front camera washer (SVT Raptor, 2012+) | 41 | Power distribution | 15A |
| 4×4 electronic shift | 20 | Power distribution | 20A |
Assignments vary by trim, engine and options. Your box cover label is the final authority for your specific truck.
If you have a 2006, 2010, 2011 or 2013 F-150 instead, the fuse numbers on this page will not match. See the 2006 Ford F-150 fuse box diagram, 2010 Ford F-150 fuse box diagram, 2011 Ford F-150 fuse box diagram or 2013 Ford F-150 fuse box diagram for those model years.
