back up lights

[joecool]

I just had a thought on that actually. It may be totally insane, I don't know...
Would it be possible to install a relay into the factory wires for the back up lights? So that when you put it into reverse, the power to the stock lights trips the relay for your better/useful lights, thus activating the independent (Read: safe and not melty) power supply to the auxillary lights?

Then you could (Maybe i don't really know) wire up a seperate switch to trip just the relay, without the stock lights coming on.

Not that anyone would EVER flash bright lights at the person tailgating you on the highway. Although, it could be amusing... if no one died. Of course if it was just for the purposes of say... setting up camp then it's all good

Yes, that is a good, safe, and reliable way to do it. That's how I plan on doing mine, whenever I get around to it.

 

[dude in an xj]

 

[Starscream]

http://i78.photobucket.com/albums/j115/40xj/101_1530.jpg

Best yet. :thumbup:

 

[87baseomatic]

no current photos but I have one square hella 55w driving lamp tucked up under my bumper on the drivers side. Its tucked up just enough to see but not get beat up too badly inthe woods. Its just tapped into the stock reverse lights for now. It does the job although the light shines a little higher than I would like. I plan on doing the oldsmobile ones by the liscence plate. Stock reverse lights and tinted windows suck for visibility when backing up.

 

[EMSJEEP]

Tap off the reverse light wire to a realy input through a diode. That way the lights will be powered directly from the relay's source instead of the harness. Then tap into the section of wire between the new relay and the diode and run that wire to the (+) wire of a second realy that can be tripped with a switch of your choice. My setup also has a switch that interrupts the auto on with reverse lights function so that they only go on with reverse lights when I want them to. Without the diode you might wind up powering the stock reverse lights with the manual on. There are other threads about this, one has a diagram.

 

[dude in an xj]

I used this wiring diagram from KC.

http://www.kchilites.com/store/faq/instructions/517_backup.pdf

 

[AlabamaDan]

So, the way I understand it is this. You have power coming directly from the battery to a relay. Then from the relay power goes out to the lights. You use a smaller load power wire to trip the relay, such as tapping into your stock reverse lights. With this setup the extra lights would come on automatically when the stock reverse lights come on. Right?

Now to modify it some is to have a second wire come from a switch on the dash to trip the relay also. In this manner you could use them to set up camp or something. Right?

Now I have lights that work when I'm in reverse or when I flip a switch in the cab.

 

[VinceYJ]

Yes ABDan.
Relay's typically have 5 "pins". One for a fused power from the battery. One for a fused and switched "input" to trip the relay. Two for power output (to lights). And one for a ground.
If you hook the wire tapped from your reverse lights to the "trip" pin on the relay then they will come on when the reverse lights power up.

 

[AlabamaDan]

Can you just have two wires coming into the "trip" pin on the relay? One from the stock reverse lights and one from the cap switch?

 

[dude in an xj]

Yes ABDan.
Relay's typically have 5 "pins". One for a fused power from the battery. One for a fused and switched "input" to trip the relay. Two for power output (to lights). And one for a ground.
If you hook the wire tapped from your reverse lights to the "trip" pin on the relay then they will come on when the reverse lights power up.

Relays typically have 4 OR 5 pins. I have installed 4 relays for various things and they are all 4 pin. It all depends on your application if you will need 4 or 5 pin relay. Also, there are 2 different 5 pin relays. One has (2) 87 pins and the other has an 87 and an 87a pin.

Some information on Bosch Relays.
http://jeepxj.info/bosch%20relay.pdf

Relay 101
http://www.eurekaboy.com/f250/relay101.htm

 

[Gojeep]

Can you just have two wires coming into the "trip" pin on the relay? One from the stock reverse lights and one from the cap switch?

You can but it will also feed power back into the stock reverse lights so they will come on as well when you switch on the manual over ride switch. If you dont want that to happen, just fit a diode on the wire coming from the stock reverse lights to the relay. A diode works like a one way valve so you face it to let power 'flow' to the relay to trigger the relay when the stock reverse lights are switched on, but the diode will stop power 'flowing' back down that wire to the stock reverse lights when the manual switch powers the relay.

 

[Begster]

I don't know why everyone is saying you need a relay if you are taping into the stock harness. Some back-up lights that you can get at Wallmart or Autozone just tap right into the stock wire with a splicer, and uses an inline fuse. Not a big deal.

 

[EMSJEEP]

I don't know why everyone is saying you need a relay if you are taping into the stock harness. Some back-up lights that you can get at Wallmart or Autozone just tap right into the stock wire with a splicer, and uses an inline fuse. Not a big deal.

and this is still a bad idea no matter how many people like to do it....lets end this once and for all...lets say that the harness wire is 18 ga which I believe it is. That 18 ga. wire can hold a load of 2.3 amps in an ideal world. Now...add two 55watt lamps, 110watts at 12VDC is 9.2 amps, now add to that the stock reverse lights. It might work, it probly will work, but its not a good idea, even worse if you plan on running the lights for long periods. Its no big deal, do the smart and safe thing and do this project the right way.

 

[dude in an xj]

and this is still a bad idea no matter how many people like to do it....lets end this once and for all...lets say that the harness wire is 18 ga which I believe it is. That 18 ga. wire can hold a load of 2.3 amps in an ideal world. Now...add two 55watt lamps, 110watts at 12VDC is 9.2 amps, now add to that the stock reverse lights. It might work, it probly will work, but its not a good idea, even worse if you plan on running the lights for long periods. Its no big deal, do the smart and safe thing and do this project the right way.

and to add, you won't get the full potential out of the lights w/o a relay.

 

[1985xjlaredo]

http://www.golight.com/products/golight.html
These are the best lights ever. They light up everything around you like it was daytime. One on the front in the middle and one on the rear. Good for those idiots with there brights on too!

 

[cal]

I don't know why everyone is saying you need a relay if you are taping into the stock harness. Some back-up lights that you can get at Wallmart or Autozone just tap right into the stock wire with a splicer, and uses an inline fuse. Not a big deal.

And everyone knows Walmart is the sign of quality

 

[Begster]

It might work, it probly will work, but its not a good idea, even worse if you plan on running the lights for long periods. Its no big deal, do the smart and safe thing and do this project the right way.

It does work, and honestly how long do you stay in reverse for? A couple of seconds here and there isn't going to bother me at all enough to go change my wiring. The lights aren't drawing the full 55w when turned on, because as you said the wire can only supply about 2.3 amps. Dude in an XJ said this too, and its true, they aren't extremely bright, but they do a good enough job over my stock lights which are blocked by my black out covers. Should I need to use the lights for a long time, or stay in reverse for a long time, I have a switch that can turn them off, then turn them onto battery power so the stock reverse wire isn't utilized. With them on through the battery I get the full 55w and they are nice and bright.

Now, I agree that if you want to just wire it to the reverse and utilize the full wattage, then using a diode would probably be best. But its not like they won't work without one and its the end of the world to not use them.

 

[EMSJEEP]

[FONT='Verdana','sans-serif']There’s half assed and then there is professional grade project planning and execution, if you plan to minimize project time by duct taping the lights to the rear glass then by all means leave no safety factory in your choice of wiring. As the lights suck amps the wire gets hotter and hotter, and if the load is too great and it is not fused at some point the wire will act just like a fuse of thinner filament and will melt through spark and start a fire. If 10 extra minutes and a do-it-right mentality is more effort than the project is worth that’s your choice, but for future searchers and observers I want to make it clear that there is a right way to do this, there is a safe and most efficient and effective way to do this and pulling 3-4x the recommended load through a stock harness wire is not that way. The amount of safety you factor into your project is your call, but personally I like to know I can depend on a system if and when the time comes when I need it to perform without question or issue.[/FONT]

 

[JEONLYEP]

There’s half assed and then there is professional grade project planning and execution, if you plan to minimize project time by duct taping the lights to the rear glass then by all means leave no safety factory in your choice of wiring. As the lights suck amps the wire gets hotter and hotter, and if the load is too great and it is not fused at some point the wire will act just like a fuse of thinner filament and will melt through spark and start a fire. If 10 extra minutes and a do-it-right mentality is more effort than the project is worth that’s your choice, but for future searchers and observers I want to make it clear that there is a right way to do this, there is a safe and most efficient and effective way to do this and pulling 3-4x the recommended load through a stock harness wire is not that way. The amount of safety you factor into your project is your call, but personally I like to know I can depend on a system if and when the time comes when I need it to perform without question or issue.

What he said, X2