2012 F150 Fuse Box Diagram: Exploring the Fuse Boxes

2012 F150 Fuse Box Diagram: Locate all the circuits served by each fuse

In this article, you’ll see the 2011 F150 fuse box diagrams for the battery junction box (BJB)/power distribution box under the hood, as well as the passenger compartment fuse box/body control module (BCM)/smart junction box located under the dash on the passenger side of the vehicle.

Let’s start with the one under the hood. Just pop it open and take a look in the center of the engine compartment, directly above the radiator. That’s where you’ll find the power distribution box. It’s like the nerve center for your truck’s major systems—things like engine management, emissions, and ABS brakes are all controlled by the fuses in this box.

Now, for the second fuse box, crawl under the dash on the driver’s side. It’s tucked away in the footwell. This one takes care of all the interior electrical stuff like the radio, power windows/locks, climate controls, and those handy courtesy lights. It’s essential to give both of these fuse boxes a once-over every so often to make sure none of the fuses are blown. If your electrical gadgets aren’t acting right, it might be a sign that something’s amiss with the fuses.

To learn more about automotive fuses, see this article
To learn how to check a fuse visually or without removing it, see this article

Find the most commonly replaced fuses here

The fuse box diagrams and tables below show all fuses in the battery junction box and body control module, along with all the relays. But most DIYers are looking for fuses and relays for the lights, power ports, and the blower motor.  I’ve listed the most commonly checked/replaced fuses here to save time. I’ve also listed the most commonly replaced bulbs. A blown fuse or bulb are the two most common reasons for lighting issues.

BCM = Body Control Module under the dash. BJB = Battery Junction Box under the hood

• Backup Light: Fuse #15 (BCM) 15A,
• Blower Motor: Fuse #51 40A (BJB)
• Front Parking Lamps: Fuse 30 15A (BCM)
• Headlight Low Beam Passenger Side: Fuse #16 10A (BCM), Bulb #H13 (dual filament for high and low beams)
• Headlight Low Beam Driver’s Side: Fuse #17 10A (BCM), Bulb #H13 (dual filament for high and low beams)
• Headlights High Beam: Fuse #39 15A (BCM), Bulb #H13 (dual filament for high and low beams)
• Horn: Fuse #22 20A (BCM)
• Rear Parking lamps: Fuse #40 10A (BCM)
• Power Ports: Rear: Fuse #72 20A (BJB), 110V power point Fuse #33 40A (BJB), Instrument Panel: Fuse #65 20A (BJB), Cigar Lighter #22 20A (BJB), Center Console #66 20A (BJB), Overhead #18 10A
•Right turn signals and stop lamps Fuse #13 15A (BCM)
•Left Turn Signals and stop lamps Fuse #14 15A(BCM)

2012 F150 Fuse Box Diagram for Battery Junction Box

The Battery Junction Box is located in the engine compartment on the driver’s side near the brake fluid reservoir. The Battery Junction Box is also referred to as the power distribution box. It houses fuses for many of the truck’s main systems like engine management, emissions, and ABS brakes.

This view of the battery junction box shows both fuses and relays. To view just the fuses, scroll down to the Fuse Diagram for the UnderHood Power Distribution Box

How to find your fuse and the devices served by that fuse

There are 62 fuse slots in the Battery Junction Box. The chart shows only 10 to speed up load time. Here’s how to find the fuse and circuit you want.
1) Change the number of entries showing (in the Show Entries Box) to 100 and scroll the list.
2) Enter the name of the component you’re searching for in the Search box.
3) Use the Next/Previous buttons at the bottom of the table

A note about fuses, battery power and keep alive memory

If you disconnect the battery or remove the PCM fuses from the fuse box, the PCM will lose its adaptive memory and baseline throttle body position. You can avoid this by providing backup power using a jumper pack and an inexpensive OBDII cable. See this article for more information on providing backup power to prevent the loss of adaptive memory. Or, you can perform a throttle body relearn procedure and then drive the vehicle so it can relearn the new adaptive memory settings. See this article for instructions on how to perform a 2012 F150 throttle body relearn procedure.

2012 F150 Fuse Box Diagram for Body Control Module

The battery control module (BCM) is located inside the cabin under the dash. It’s considered a smart junction box, meaning that it receives a request from a switch like a light switch or a door switch and then switches power to that device.

In other words, the switch doesn’t actually switch power to the device. The switch closure just acts as an input or a request to the BCM. By using very low-current wire between the switches and the BCM, carmakers save on wiring costs and lower the vehicle’s weight.

The BCM has 48 fuse slots, but the chart shows only 10 to speed up load time. Here’s how to find the fuse and circuit you want.
1) Change the number of entries showing (in the Show Entries Box) to 50 and scroll the list.
2) Enter the name of the component you’re searching for in the Search box.
3) Use the Next/Previous buttons at the bottom of the table

2012 F150 Fuse Box Diagram for High Current Battery Junction Box

2012 F150 Fuse Box Diagram for Auxiliary Battery Junction Box

Looking for more information on your 2012 F150? Click here for the Firing Order, Engine Layout Diagram, Spark Plug Gap and Spark Plug Torque specs.

Tips to diagnose electrical issues on your 2012 F150

If your power windows don’t work
• In previous model years, Ford used a 30A circuit breaker to provide power to the windows. However, starting in the 2012 F150, they went back to using fuses for the front windows.

The fuse for the driver’s side power window is #1 30A in the BCM, and the #3 30A for the passenger side window. However, Ford still uses a 30A circuit breaker for the rear passenger and driver’s side windows and the power sliding rear window.

The circuit breaker is located in the BCM in slot 48.

If your blower motor doesn’t work
The blower motor gets its power from the blower motor relay #3 in the battery junction/power distribution box.

If the circuit you’re working on contains a relay
• A simple way to test a relay is to swap in a similarly shaped relay and see if the component works.
• If that doesn’t work, remove the relay and test for power to the relay control coil and contacts using a multimeter. For more information on relay testing, see this article.
©, 2018 Rick Muscoplat