HOW TO CONVERT YOUR FACTORY LIGHTER SOCKET TO BE KEY-SWITCHED

--------

From the factory, Ford wired the cigar lighter socket onto the same circuit as the horn. It's always receiving power, and is usually fused with a 20 amp fuse. This is fine if you only occasionally use your lighter socket, but if you have accessories that you want to leave hooked up all the time (cell phone charger, GPS, DC-to-AC inverter), but don't want them running your battery down when the truck is off, then this project might be useful to you.

Below are the steps involved in wiring up your lighter socket to be switched on and off with the ignition key. You'll only need to run a positive 12v wire from the socket to the fusebox; you'll leave the factory ground wiring alone.


What you'll need:


- Ford push-on terminal end, like what your lighter socket currently uses to receive 12V. You can get a package of them at auto parts stores, from the junkyard, or in my case, just cut off the one that goes to the lighter socket and use that. (If you use the last method, leave yourself enough wire to work with!)

- A length of wire the same gauge as the factory lighter socket wiring (12-14ga.) to run from the lighter socket to the add-on fusebox

- A crimp-on butt connector to connect the push-on terminal to the aforementioned length of wiring (alternatively, you can choose to solder the connection, it's up to you)

- A spade connector, or whatever style connector you'll need to connect the new lighter socket wiring to the add-on fusebox

- One 20 amp fuse


--------


1. If you bought or have a push-on terminal end, use the butt connector to connect it to one end of the length of wire. If you do like I did and use the one for the factory lighter socket wiring setup, you'll need to cut off the terminal leaving enough wire to work with, then crimp/solder it to the length of wire. Put tape over the end of the wire you just cut so it can't short to ground, since it's still going to be always hot.

2. Connect the other end of the length of wire to a circuit on your new fusebox and put in a fuse, 20 or 30 amp.

3. Find something that plugs into a lighter socket (cell phone charger, cigar lighter, etc.) and check that it works.

4. If it works fine, you're good to go. If you blow a fuse, check your wiring as well as the ground wiring for the socket.
If you have problems with the ground wiring, you can just run a wire from the ground terminal on the socket to a good ground.