A Few ??? about a Back Up Light Install

I want to add a couple of back up lights to my truck. Although I'm not using KC lights, I'm following this wiring diagram, including the switch wiring: http://www.kchilites.com/wp-content/uploads/2010/04/517.pdf .

This setup lets you have the back up lights come on with the reverse lights. The switch is flipped to turn on the back up lights independent of the other lights. I would like to use this switch : http://www.grainger.com/Grainger/CARLING-TECHNOLOGIES-Rocker-Switch-10C585 , a three position on-off-on switch, so I can turn the lights off when not needed.

Will that switch work with the wiring diagram above? Do I need to do anything different to make it work as desired? Also, can I use a fuse tap for the switch or does it need to be run to the battery?

I'm also considering another non-lighted switch. Is there anything different about wiring a non-lighted switch in this instance?

Thanks!
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Sorry about the double post-not sure what happened there.

 

That KC diagram is all fucked up.
The backup lights will switch properly with the stock lights, but when the stock lights are off, the relay will just connect your switch to the battery.

You need a 2nd relay to run manual on/auto/off the lights.
I'll see if I can work up a circuit for that.

 

Okay, I can do a circuit that only uses one relay, but it may not work with your lighted switch... it depends on how the switch is wired internally, and that information is not available on the Grainger listing.

I'll keep looking

 

I also have an unlighted switch like this: http://www.swps.com/540-srj.html .
I wouldn't mind using that one.

I also see DPST and DPDT switches and wonder if a double throw switch is what i should be looking for?

 

Ya... Won't work with a 4-terminal lighted switch.

The way to do what you want would be to connect the center terminal of the switch to pin 86 on the relay, connect the stock backup light tap to the "bottom" terminal on the switch, and a fused (5a) wire from the battery to the 3rd switch.

In the center position, the relay never gets power. In the "down" position, the backup lights activate the KCs, in the "up" position, the KCs are on 24/7.

The problem is, the lighted switches assume that you are connecting your power source to the center terminal and the lights are wired to the end terminals.
Your switch would be lighted 24/7 and drain the battery.

Worse, the way the Carling switch is wired with the common ground on the two lights, you might get some backfeed through the lights and the switch would flow some current to the stock backup circuit 24/7.

Here's the wiring on that Carling switch... you can see the issue when you look at my drawing.




You can do it easily with a non-lighted switch:

 

You need a SPDT (or DPDT, doesn't matter) for my diagram.

 

Thanks for that diagram-it makes it look fairly easy to do. One question, can the 5 amp line running from the switch to the battery be wired into a fuse tap, one that is only hot when the ignition is on?

Thanks Again!

 

Ya... it's just powering the relay coil which draws next to nothing.
I like having these wired hot 24/7 because it can be helpful loading ATVs on a trailer, but without a lighted switch, it's possible to forget that it's on.

 

Perfect. Thanks, Rich!

 

Ok, one more quick one. The white wire in your diagram, since it's not carrying any current, can it be smaller wire like 18?

 

18 is fine, but be careful in routing to protect it from stress and edges.
I will not use anything smaller than 18ga, and try to stick with 16ga or heavier in a vehicle simply for durability.
Never use a solid-core wire... that belongs in walls and other areas that don't move. Always use stranded in a vehicle.

 

Yea, all my wire is stranded.

I think I've got a handle on this thanks to you.

 

Look at that help... +1 to you Rich

 

Can someone show me(pics would be great) where the backup relay is on a 98-00 PLEASE! I know where the switch and fuse are but not the relay. My backup lights went out on me and im trying to hunt down the problem. fuses are good lights are good. Yet to check switch and can't find relay. THNX!!!

 

I don't believe there is a relay on either a 1st or 2nd gen truck......not needed for two little bulbs in the stock reverse lights. I would focus on your switch.

With a stick shift it should be real easy to check, just two wires.

 

Where is the switch???????