Ford F-150: Fuse Box Diagram
Whenever you run into an electrical problem, the fuse box is the first place to look. Here is everything you need to know about fuses in your Ford F-150 truck.
This article applies to the Ford F-150 (2004-2014).
Fuses are key to your truck's electrical system and to keeping everything that relies on electricity working properly. Your fuse box or boxes will house many different fuses, each one controlling one or a group of items similarly related. A fuse works by allowing an electrical current to flow through a piece of metal in between two metal prongs. When too much current flows through the metal bar, it overheats and breaks thus causing a shortage in the system. Fuses are crucial to protect both you and your truck. If that metal bar didn't break, it could overheat the wires and start a fire.
Fuses come in all shapes and sizes. However, the majority of fuses you'll find in your truck will be a form of a blade fuse.
You'll notice that the blade fuses not only come in all different types but also in a lot of different colors. The size is normally dependent on the amperage they're rated at, usually the higher the amperage, the bigger it is.
The color, similar to size, also is used to denote amperage. This is really useful for when the number on the top has worn off. However, be warned that the color coding is only semi-standard. This means that majority of brands follow it, but some color/amps may vary slightly brand to brand.
Locating the Fuse Box
Most trucks will have two to three fuse boxes inside the truck and under the hood. Generally, the fuses inside the truck control things inside the truck and, likewise, the ones under the hood control the electronics under there.
Due to both the locations and the layout varying with every single body style, it's best to refer to your owner's manual for the location of the exact fuse you need to find. If you don't have an owner's manual, you can download one for free here.
Diagnosing a Blown Fuse
The easiest blown fuse to diagnose is one that had the center bar break. However the break isn't always that easy to see because sometimes it'll occur closer to one of the fuse legs. The break can also be covered up by a burned bar which will darken the plastic too much to see it.
Because it's not always easy to diagnose them just by eye, I recommend picking up a cheap fuse tester. They're normally only a few dollars and small enough where they won't really take up room in a glove box. A lot of the cheap ones will also be dual function, where they not only test the fuse but also have a fuse puller on the other end.
Depending on what type you get, it'll have different ways to notify you that the fuse is good or if it's blown. Some will have a light that turns green when the fuse is good, some will turn red when it's bad, others will beep when it's bad.
Fuse Box Diagram
Why Did the Fuse Blow?
The most common cause of a fuse blowing is normally due to old age. However, if you are constantly replacing the same fuse over a short period of time (less than a month), you may have an electrical problem elsewhere. This is normally due to a frayed or loose wiring causing it to not make proper contact.