Wiring 500 Watts of aux lights from scratch.
5x 100Watt lights
2x 30A relays
2x SP/ST switches w/red LED
15’ #16 primary wire RED
15’ #16A primary wire BLACK
20’ #10 Wire (10AWG) white
20’ #10 Wire (10AWG) black
2x Splash proof inline ATC fuse holders
1x 20A ATC fuse
1x 30A ATC fuse
1x “add a circuit” ATM fuse holder
30x #12 Gauge Butt Connectors
20x #12 Gauge female quick connect terminals
8x ATM tap splices
3x ½”x10’ black wire protectors
Heat shrink various sizes
4x #4 Gauge ring terminals
– The amount needed varies on the guy doing the install, so buy more that you think you’ll need
First thing I did was remove the positive connection from the battery and lay a leather glove across the terminal so that if I accidentally bumped it while working on my wiring, I wouldn’t get lit up.
Next up was the always-on fused power going to the #30 tabs on the relays. Because I wanted to run lights on two independent switches, I took a 4 gauge ring terminal and attached two slightly different lengths of #10 wire, crimped and shrinkwrapped them so now two wires connected to one terminal. The terminal I used was big enough for two stripped 10AWG wires to sit side by side. Then I spliced in the inline splash-proof fuse holders, crimped and shrinkwrapped them and added a female disconnect to the end of each one and attached them to my relays.
Now that I had fused power to my relays, I needed power to my switches. People told me I could just tap into the cigg lighter circuit, and you can, but that would involve knowing which wire it was and tapping into it. I saw more wires than I ever expected back there and had nightmares about cutting the wrong wire time after time, making splices and creating chaos behind my dash. So in the end, I decided to just tap into an IGN/ON circuit at the fuse box with an “add a circuit” ATM fuse holder and run that into the cab. It’s basically just a fuse holder that has a wire sticking out of it. Since the additional load on the circuit I picked would be so small, I used the smallest fuse I had on hand and ran the wire into the cab through the foam hole on the driver’s side and spliced it so that both supply tabs were running from the same circuit.
When I split the #16 primary wire, I used a #12 Guage Butt connector. If you strip a little extra sheathing, then twist and fold the #16 wire coming from the fusebox back onto itself, you'll find it fits a #12 (yellow) connector pretty well. Strip the two wires for your supply as you usually would and they will rest snugly inside the other end of the #12 connector. Saved me about 8' of wire doing it this way. If you look at the pic below, you'll see one wire still has a little bit of the yellow connector showing because I suck at using heat shrink
I attached wires to the load tabs on my switches, fished those through the firewall and out to the #86 tabs on my relays, connected them then ran grounds for the switches to a ground nut on the floor by the clutch pedal.
I grounded both relays in the same way I powered them. I used another 4 gauge ring connector and grounded everything to a factory grounding nut on the passenger side and attached the ends to the #85 tabs on my relays.
Now that there was power running to both the relays, IGN/ON power supplied to the switches, and everything was grounded, I needed power running to the lights. I fished a white 10AWG wire down the body and popped out just below the marker lamp. I used tap splices at each light so that there would only be the one wire attached to the relay, instead of one for each light.
Ran grounds to each light from the factory grounding nut under the hood and tapped into each light with a splice and that was it for wiring.
I cleaned everything up with some black wire protection tubing, zip tied everything in place and called it a done deal.