Once I installed my new tonneau cover, the need for bed lights became obvious.

I found a nice set of LEDs on eBay. 4-12" strips with a Auto off (15 min) switch. Looks like a nice setup.

My question for the knowledge/experience base of the forum:

Is there an "Always HOT" or "Ignition-on HOT" wire under the bed of the truck that I can tie into?

I'd rather not run up to the battery or even the cab, unless the ease of this somehow escapes me. I've done wiring on cars for nearly 40 years, but always inside of the body panels save fog/driving lights.

I was planning on tying into the Parking/taillight wire of the trailer light circuit for simplicity's sake. Thought I might inquire as to an alternative before I break out the waterproof butt connectors.

If I do go right to the battery, is there a preferred place for the wire to enter the engine compartment once I run it along the frame? As previously mentioned, the kit switch has an Auto-Off feature so I'm not too worried about leaving the lights on and draining the battery.

If running the power wires into the cab is the best way to go, where's the best wire entry and tie-in point?

I do have wiring diagrams, but am hoping that a simple question might steer me in the right direction first.

In the past I used to just dig in a figure this stuff out. Plus, 95% of my experience is on Chryslers, Jeeps, and my '81 FIAT Spider that I've had since '85. I know different makes sometimes require (prefer) certain techniques when it comes to auxiliary power, i.e. to ground to chassis or not.

What is the "rule" for running aux lighting power on Ford trucks in this instance (low amperage occasional use)?

This forum is a great tool for planning jobs, and it's fun to use.

Thanks in advance for any advice.

 

I took the lack of replies despite nearly 200 views as a passive/aggressive kick in the pants to search the forum for answers.

Sounds like the best thing to do is to tie into the trailer wiring brown wire circuit in that I'm wiring low-draw lights.

Might go to the battery, but I will definitely add an inline fuse basd on what I've read.

Thanks for the help.

 

I ran a wire all the way to that battery with a fuse. My advice, run 10 gauge now in case you need to power up something else later!

 

Why not change the interior lighting to LED, run a few strips of LED's in the bed, and tie them into the interior lighting wires? By changing to LED's inside, you will no doubt be able to utilize the stock wiring harness / fuse with the added LED's in the bed. On the plus side, you will even be able to use the interior light switch to operate them!

 

I'll check out what interior lighting I have tonight.

New-to-me truck; haven't really looked at less-than-critical systems all that much yet)

Would that involve changing the instrument panel lights to LEDs as well?

 

If I do follow AnthraxBird's suggestion, at what point should I tie into the interior lighting circuit?

I'm well-experienced in auto wiring, but not on Fords. Experienced enough to know that each make has its quirks, and "Do's and Don't's"

Also, I've never dealt with running wiring from a truck bed to the cab. I.e.: What level of weatherproofing / tie down measures are recommended in making the jump? Similar to wiring fog lamps and such?

Please pardon the "Pickup newbie" question, but I know enough to recognize that assumptions can be problematic. Most of my wiring experience is within the confines of body panels.

Thanks in advance for any advice.

 

Mike, you don't say if your truck has the tow package. If it does, it will have a 7-pin trailer plug under the bumper. And, one of the wires into it will be +12V if the ignition switch is on. It is fused with a 30A fuse. There is also a Gnd wire to that plug but you could use any convenient frame ground.

If you don't have the tow package, it's easy to run a wire up to the battery. I've run one for a backup camera on my old 2005 truck and just tied the wire along the frame, following the wires to the taillights. As I recall, there is an opening in the firewall on the driver's side in the engine compartment you can bring the wire up through, then, you can go directly to the +12V terminal of the battery, with an inline fuse.

Hope these thoughts help.

- Jack

 

Yes I do have the tow package.

I hadn't even considered the 7 wire thingamajig. My two trailers are 4 wire so that's the only one I verified. I've never had a 7 wire trailer, so I guess I never really thought about the purpose of the other wires. Always assumed they were for the extra turn signal circuits. and other such things.

I'll go through my wiring diagrams and figure out which one is the ignition hot wire.

That sounds like the simplest way to go.

Also, thanks for the note on the access into the engine compartment.

 

You're welcome, Mike. You MAY need to insert the 30A fuse into that trailer circuit if it's never been used. Ford generally puts the fuse in an envelope in the glove compartment, but you may not have it. Here's a link to the most common wiring scheme: https://www.etrailer.com/question-363.html With the ignition ON, you should be able to get 12V with a multimeter +probe on the 1:00 OClock pin and the -probe on the 7:00 OClock pin.

- Jack

 

Looks like the fuse is there, but the corresponding relay is not. Assuming it's the Trailer Tow Relay / Battery Charge one.

I'll have to junkyard one of those. All 3 of those large replays are basically the same part, right?

This cold snap we just had may well delay the install until spring anyway.

I've printed diagrams and filed them away until I can get to it.

Thanks for the help!

 

Yup, that's the relay. You might test things by transferring one of the other relays to that position. And, I doubt the relay is expensive if you wanted to get one at an auto parts store. I didn't know if you had a relay there, so I didn't mention it.

- Jack