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Help wire back up lights!

Discussion in 'Strobe Lighting' started by JMHConstruction, Jan 5, 2016.

  1. JMHConstruction

    JMHConstruction PlowSite.com Addict
    Messages: 1,722

    Hey guys, hoping someone will help me out here. I installed back up lights on my truck and I thought everything was going good. I used a photo from Google to help me with what wire goes to what.


    It's the first picture. I can't upload the picture from my phone. What I want is my 3 way switch to either turn the lights on/lights off/lights on with reverse. So I wired it up like the diagram says but the switch is aux lights on/off/stock reverse lights on. I'm not sure what I did wrong or how to fix it. Please help!

    I tried to edit the link to work, but it doesn't. You'll have to copy and paste
    Last edited: Jan 5, 2016
  2. JMHConstruction

    JMHConstruction PlowSite.com Addict
    Messages: 1,722

    Think I figured it out. I need a diode.
  3. JoeG3

    JoeG3 Senior Member
    Messages: 156

    I can't get the photo to load on my phone but you shouldn't need any diode. The easiest way is to tap into the trailer light harness, connect a wire from the reverse feed to side A of the switch. Find a constant +12 feed (you can tap the running light wire from the trailer harness so they turn off when you turn the truck lights off) to side B of the switch. Take the common from the switch and connect to your lights or if you have a lot of lights you might need to go through a relay but only 1-2 lights can usually come right off the trailer wiring.

    Hopefully this helps.
  4. TJS

    TJS PlowSite.com Addict
    Messages: 1,440

    This has been covered many times. Might help if you give more information. Such as what you are working on. If you have a factory 7 pin trailer connector it is pretty easy. Use the reverse wire from the 7 pin to trigger your relay, then to feed the relay use the 7 pin connector (charging feed wire to power the relay for the lights). Get the 7 pin connector at west marine. 6.99 for the connector. The diagram is in the box. See my signature for hitch light and I show how I did it.
  5. JMHConstruction

    JMHConstruction PlowSite.com Addict
    Messages: 1,722

    Here is more info.

    Hooking up 2 cheap halogen lights.
    I have aux lights straight to the relay.
    Relay has direct power with fuse.
    Relay to switch "bottom on".
    Relay ground.
    Switch has direct power to middle prong with fuse.
    Spliced into reverse light wire and ran wire to "top on".

    It turns the lights on without being in reverse. It turns the lights off. But on the second on position it turns the truck reverse lights on without being in reverse. I was originally going to hook into the trailer wire, but after a google search on what wire it was, I found 4 different answers. I knew for sure what was positive on the reverse lights.
  6. Too Stroked

    Too Stroked Senior Member
    Messages: 573

    I think what TJS meant was "What kind of vehicle are you working on?"
  7. kolwnmstr

    kolwnmstr Senior Member
    Messages: 223

    Do you always want them to come on when you are in reverse?
  8. JMHConstruction

    JMHConstruction PlowSite.com Addict
    Messages: 1,722

    What would difference in vehicles have to do with anything? Not trying to be a smart ass, just curious. It's a 99 ram 1500. The extra detail on how i wired it might help too, so win win. I want to be able to set them to either always be off, on even when not in reverse (for loading tools and such in the dark), or on when I go to reverse.
  9. JMHConstruction

    JMHConstruction PlowSite.com Addict
    Messages: 1,722

    I tried to search here, other forums, and google. All I could find here was wiring it to always come on in reverse, or off. Nothing with a 3 way switch. I may have searched for the wrong thing though. When I googled it I found a bunch of diagrams exactly how I wired it, but I'm obviously wrong.
  10. TJS

    TJS PlowSite.com Addict
    Messages: 1,440

    It has a lot to do with what you are working on. If you want answers supply some more information. Simple as that. Do the 1500 RAMs have a 7 pin trailer connector(the seven pin wire harness has a charging wire in it that can feed extra lights via the relay) ?. I do not know but you do. Have you searched plowsite :backup lights, reverse lights etc, there are tons of posts on this. Have you looked at my signature where I post a link to the hitch light set up. There are links as well as some information on how to wire reverse lights too and I even refrer to Wicked warnings vid on this.

    Not sure why you want to be able to switch them on when not in reverse, but that is your choice(maybe you have a sander, but again I do not know). Mine only come on in reverse. I do have a swtich in the cab that "removes" the ground from the backup alarm so I can "turn it off" not to wake up the residentials. I turn the gound back on when I need to back up with audible. Not trying to be a wise guy either but we have no idea what you are working on and what your final goal/result is. Not sure what switch configuration or relay you are using. Some relays ar NC (87/87a) or NO. Post pics of what your diagram is and what the actual components you are using.
    Last edited: Jan 6, 2016
  11. TJS

    TJS PlowSite.com Addict
    Messages: 1,440

    I think this is what you want. I drew this up real quick. You need a double position double throw switch(the one with 6 terminals). This should eliminate the need for a diode so you do not back feed your single throw switch and subsequently turn on the lights when you do not want to. I have not tested something like this but it should work. Disclaimer: I did not test this, not responsible for user error or eletrical issues or fire where animals or humans were maimed or killed.

  12. joshg

    joshg Senior Member
    from VT
    Messages: 142

  13. chuckraduenz

    chuckraduenz Senior Member
    Messages: 345

    I did this to my 13 chevy 2500. made my own switch panel and my own harness. I ran the reverse signal from the factory reverse light 7 way trailer plug on the rear. ran a wire to my switch panel. used a single pole on/off/on switch. used the center pin on the switch for the rear lights. then ran a hot wire to the top pin and the reverse light signal to the bottom pin. then ran a wire all the way back and split it off to ea light. so it can come on in reverse all the time, I can turn it off, or turn it on. I didn't need a relay or a big double pole switch. to much un needed stuff. amp draw is 2amps before some one says you need to relay my set up. its also fused as well. been working for 3 yrs no issues.

  14. JMHConstruction

    JMHConstruction PlowSite.com Addict
    Messages: 1,722

    Sorry guys, I never posted an update.

    When I was wiring the lights, going off the diagram from the picture (I know the link didn't work, sorry) it had 2 wires in the wrong place on the switch. After starring at it forever it just hit me. After switching the 2 wires it works great. Actually had a truck take out my rear end about a month ago, and he took out both tail lights. Been using the auxiliary reverse lights ever since (still fighting with his insurance) and they have been working flawlessly.
  15. cutshortlandscaping

    cutshortlandscaping Senior Member
    Messages: 118

    We just cut the reverse lights in our tail lights than put the positive for the new reverse lights and the tail lights together make the ground and there you go
  16. Too Stroked

    Too Stroked Senior Member
    Messages: 573

    You will find that with many newer vehicles (late model Ford Super Duties for instance), the Lighting Control Module doesn't like that kind of thing and it will cause all sorts of problems.
  17. cutshortlandscaping

    cutshortlandscaping Senior Member
    Messages: 118

    Really never knew that what if you put a inline fuse between the new lights and the factory installed lights?
  18. dieselss

    dieselss PlowSite Fanatic
    Messages: 11,390

    Fuse isn't going to help, the issue is the extra power draw. Best running separate wire with switch and relay.