I'm working on hooking up my backup lights...I have a switch in the dash that is an On-Off-On switch. So one feed is a constant 12v but I want the other feed to be an "auto light" feature where its fed by the backup light source so that they only come on when its in reverse. Where can I find a + reverse wire near the engine compartment for the backup lights without tapping in at the trailer hitch and then running it all the way back up into the dash?

 

are you using a relay near the lights? if so then you only need the reverse + wire near the relay, not the switch.

 

I have a 2 source switch that I want to use like this..

^|-Lights Always On
- |-Off
v |-Lights On only in reverse

Right now I have the lights always on part so I just need a reverse switched power source which would enable the lights on only in reverse mode.

 

Nevermind..had to stare at the wiring diagram just a little longer and i found an extra parts bag that had the connector i was looking for too. Now it makes sense how its supposed to go![sm=headbang.gif]

 

I got it hooked up but I have a question..
What exactly does the relay do??

 

Keeps the high amps at the relay and not the switch.

 

yup, you will notice A HUGE difference in brightness when using a relay!!! HUGE!!!! Always use a relay, stock wires arent thick enought to handle the amp draw from adding additional lights and stuff. Basically here is what you would do to wire a relay. you would use 4 legs of the relay, numbers 85,86,30, and 87.

85 - hookup to a solid ground, preferably to the frame of the truck

86 - switched power, either the power wire coming from a toggle switch or a wire that gets juice when you put it into reverse (for reverse lights)

87 - power out wire, run this wire to the source that needs power once the relay is energized from terminal 86. In your case this wire will run to the reverse lights.

30 - Power, run this wire directly to the battery so you have an undisrupted power source, or you can use the thick acc. wire in the trailer plug as that wire is a direct feed and has plenty of amperage.

Basically what this realy will do is the power coming from the toggle switch will energize the relay sending the full current from the relays 12 volt power hookup to the light you have connected to terminal 87.

 

Yea I noticed a huge difference. Once i played with the relay and i realized that it switched the big 12v off the battery to the lights using the switched power as a turn on lead, I hooked it back into the wiring I did. It made it MUCH brighter!!