I just got some auxiliary lights and I was going to wire them up in the morning and I was curious if it's possible to wire the power to both a switch and the reverse lights. I would like to use them with reverse lights and not have to switch it everytime, but I want them on a switch for tailgaters or any other purpose.

Can it be done?

 

Yep. I have mine wired that way. You have to have a 3 way switch (On-Off-On). You can tap into the back up lights for one of the power wires and then just bring the other one from the battery or where ever you were planning on getting it from.

I had some links to write ups for it but it seems that my old links for this website dont work anymore.

 

I made a setup for a guy on another forum not too long ago to do basically that same thing.
He had some led panels for his lights initially, but just switched over to h3 bulb lights.

I made up a circuit with isolation diodes that triggered a relay but wouldn't feed current back through the other circuit.

When the reverse lights come on, the relay triggered & the aux lights came on.
When the switch was turned on (mounted in the bed) the lights would come on any time even if the truck was off.
The relay got power directly (fused) from the battery so there was no additional load on the stock reverse wiring.

Not too complicated to wire up, just need some heavy duty diodes to handle the amperage draw of the lights... probably a 6a to 10a diode would work on each trigger wire.

 

The auxiliary lights I bought are LED's but I would like the wiring to be able to handle higher wattage halogens in case I change my mind later.

Does anyone still have a wiring diagram?

 

Buggman has it right, make a circut and use a relay and diodes. do it right and it will never fail on you.

 

I'll try to make up a diagram when I get a chance

 

Not to say anyone is wrong but to me a double throw, single pole switch (On-On) is the way to go.
Some wire, some fuses and you are good to go.

First find the reverse switch on the trans, lift the wire that goes to the reverse lights.
Cut this wire and extend both sides to reach the Switch.
Attach the wire going to the lights, the load, to the center pole of the switch.
The wire that is still attached to the trans, attach that to one of the other two poles.

Test - with the truck in reverse and the switch in one of the two positions available the lights should be on. If not double check all of the wiring.

Next step, run a fused wire from the battery to the empty pin on the switch.

Test - Flip the switch to the other position and the lights should work.

Position the switch so when the trans is switching the reverse light the dash switch will be in the down position, sort of an Off Position; when up the manual over-ride will happen and the lights will be on.

This setup can be changed but as is it will work with LED reverse Lights and OEM reverse lights of 35 watts and lower.

If you want to wire up some high wattage lights 55 watts and higher, add a relay. A relay will allow the light to burn their brightest.

Relays are easy…
The load wire from the manual switch, the wire from the middle pin, this should go to pin 85 on the relay, pin 86 should be grounded.
Run a new fused power wire from the battery to pin 30 on the relay and then from pin 87 to the lights.
Run new HD wiring, 12-ga minimum, to the lights from pin 87.
12 gauge wire will handle 20 amps so it should cover almost any pair of lights out there except the older 130 to 150 watt lights, these need a 10-ga power wires.

Fuse all power wires and use wire gauge based on the total amperage of the light draw; double it if there is a question.
Always get good grounds, bare metal for contacts or run the ground wires back to the battery; more wire yes but usually less ground problems.

So this is confusing… think it through, one switch with three pins.
One common , the lights goes center.
Two power sources (sort of) two other pins, one source to one pin and the other to the other pin.
Use large enough wire or thing will burn up besides your truck.
Fuses should be close to the power source or else when shorts happens the power will not be cut off close to the battery and again a burnt up truck.

OK too much, I will get off of the box.

IMHO you do not need a special circuit for this setup, there will be no feed back since the switch will be in one position or the other.
There is no so called “Off” position because the switch will usually be in the Trans Reverse Position or auto, sort of an off position and in that position the trans will handle the power switching.

One more thing, if you like indicator lights, get a double pole switch, one with two sets of connector on the back.
One row for the power control and the other row for indicator lights.

Luck