i don't know how hard it would be to find this wire, but would it make sense to tap the cargo light as the feed to your aux light relay. then when you turned on the cargo light you'd have a top (oem) and bottom (aux) light.

and you wouldn't have to put in an extra switch.
you could place the relay up front, and then run the load wire to the back.

 

Why not use the above SPDT relay?
Pin 30 = fused power coming from the battery.
Pin 85 =as ground.
Pin 86 =would be spliced into wire that is going to the backup lights.
Pin 87a= would run to the toggle switch then to the aux light.
Pin 87 = splice into 87a after the toggle switch.
Then all current for the light is drawn off the battery.
So when you go into reverse the relay would energize 87 and power the aux light.
Then you wouldnt have to worry about leaveing toggle switch on because
there is always power across the relay from pin 30 to 87a and you control
that power going to the aux light with your toggle switch, so if you leave toggle
switch on your light is on.
You dont have to worry about anything back feeding thru the system.

Dave

 

Here is how I did mine. Can be controlled to come on automatically with reverse, or switched on by itself. The two diodes (1N4001) prevent back-driving the reverse lights (in the tail light housing), and the other helps to prevent relay chattering.

 

i think im starting to get the idea, now what do i look for when i go into the prts store? and are the diodes already in the light itself? or is that something i have to put in it?

 

I added the diodes myself. There is a surplus electronics store around here that I got them from, but Radio Shack should have them as well.


I think this would cover pretty much everything:

Wire
Relay
Relay harness (Optional. Sometimes you can find them with a diode already in them).
Fuse & Fuse holder.
Misc crimp connectors - so you can slide wires on/off the relay easily, or splice wires that you don't want to solder.
Diodes
Wire taps (if you don't want to solder): http://www.radioshack.com/product/in...ductId=2104093
Switch(es)

Good luck,
Cartman

 

You don’t need diodes to do this if you use the relay in my last post and wire it the way I explained. If you don’t understand it I can email you a drawing.

Dave

 

I like that idea a lot. Can someone figure out a way to have them come on with the reverse lights too? I'm electrically challenged, so a wiring diagram would be very helpful.

 

It's basically the same as the diagram I posted above, but you would add one more leg (with a diode)



The diode keeps you from having your reverse lights back drive your cargo lights (and vice versa).

You could get rid of the aux switch (since you could use your cargo light switch now). You can also eliminate the master switch if you wanted as well. I added it because I don't always want them to come on.

I don't know the wire locations/colors off the top of my head, but the FSM will give you all the info you need (wire color, locations to splice into, etc).

Cartman

 

im pretty limited on electrical supplys here, the nearest radio shack is 45 min away and thats the closest electronic store around, im pretty limited to the lowes wiring and the 2 or 3 shelves at oreillys, is there anything there i can use? like that spdt relay?

 

Check this link for schematic, you should be able to print it or I can email it to you.
http://s809.photobucket.com/albums/z...ent=jpg006.jpg

Dave