PNWjeeper

Just got a set of leds and I'm thinking about putting them on the rear of my jeep. The thing is I want them to turn on with the reverse lights, when the jeep is put in reverse, and I want to be able to turn JUST THE LEDS on with a switch WITHOUT the stock lights in the housing turning on.
I know it's possible:
https://electronics.stackexchange.co...amp-12-v-diode

I'm just having a hard time picturing it in my head, if anyone understands and could draw me up a diagram that would be awesome. Or explain it a little more clearly, I'm a very visual learner so diagram would probably be easiest.

PNWjeeper

Ok after some more reading and research I think I got this. So I need a switch that does ON-OFF-ON or has he wrote it SPDT (single-pole-double-throw). When switched all the way down it would turn on and off with the reverse lights, in the middle the LEDs would not turn on but stock lights would as normal, and when all the way up LEDs would turn on but without turning the stock lights on.

Does this sound right?

PNWjeeper

How's this look?

PNWjeeper

Just realized this is wrong.
The middle should be "to LEDs" and then up and down should be "from reverse switch" and "12v constant"
So it should be:

From reverse switch
To LEDs
12v constant

Thanks for the help CF I knew I'd figure it out some way lol.

BlueRidgeMark

Okay, I see you figured out your mistake.

Not sure that's the best way to do it, but it will get it done. You are asking the existing circuit to supply ALL of the power to the LEDs, which might be a bit much for it. It all depends on how much current your LEDs draw.

I'd run power to a relay and let the existing reverse switch just turn on the relay. That way you aren't adding any appreciable load to that existing circuit. Automotive relays typically draw about a quarter amp, so nothing to worry about.

PNWjeeper

Yes and a relay was in the plan it was just more of the getting the switch to work part I needed help with.

BooGTS

You could put a resistor / diode / resistor in the signal line to the reverse light relay. Between that and your relay, put a switch to your "override" . That way you have one switch and the reverse lights will always be sure to work regardless of wherever you leave a switch.

BooGTS

Not at home to fire up the P-spice but that's the general idea.

PNWjeeper

I had originally wanted to do the diode, but that's when I ran across that site I posted earlier and decided I liked the on-off-on switch better.