How do you go about wiring the reverse lights to come on with one of the upfitter switches?

 

Hm. I'm tying into the reverse lights to put the reverse alarm on an upfitter (As it's powered by the reverse lights). I'm using a Hella relay for that, but I'm already getting power from the reverse light. You need to add power for the reverse light when none is there.

I'd run a relay that, when the upfitter is switched on, sends power to the reverse lights (whatever voltage that is..) and keeps them on at all times.. when the upfitter is switched off, the wiring goes back to standard.. (basically, switching the existing power wire to the reverse light to either being supplied power from its original source that is activated when in reverse, or switching it over to a constant power source switched on via the upfitter).

There was a thread in another forum on this board with the schematic and idea for the reverse relay. I think it'd be something similar for you, just need to find the power source for your always on and the voltage.. other guys here I'm sure know exactly where you'd find what you're looking for.

 

I have supplemental reverse lights that I use to illuminate my trailer when hitching up at night. They normally come on with the regular reverse lights.
I wired up one of the upfitter switches so that I could turn the reverse lights on without having to shift the transmission into reverse.

(It's not legal, but I have, on occasion, used the reverse switch to show my annoyance to folks who are tailgating me, and to signal meathead drivers who are behind me at night with their Hi-Beams on.)

 

Great that you included the diode. So many of the lights and accessories are computer controlled that back feeding the system by simply inducing power near the point of use will send errant signals to other items in the system. There is often times no telling where the signal will manifest itself so an ample supply of properly rated diodes is needed for aftermarket accessories and amendments to the system.

 

Something to keep in mind with the diodes is the .6 voltage drop across the diode.

 

I'm interested in shutting the reverse lights off when in reverse. At night, when backing up my 5th wheel trailer, the reflection is blinding.
I guess i would put in a n/c relay in line, controlled by an upfitter switch?

 

I would love to see pics of the diode set-up!
thnx

 

Literally, it's nothing to look at. There is a Diode that's now in line with the existing wire, and the upfitter wire is spliced after it.

I cut the Reverse wire going to my trailer connector. Then soldered the Anode end of the diode to the Ford wire that comes from the front of the truck. Then I soldered the other end of the cut Ford wire to the Cathode side of the diode. (The Cathode side is marked with a white stripe.) From there, I also soldered my new upfitter power wire to the Cathode side of the diode. The wire then goes to my supplemental reverse lights.

The Diode and the solder connections are covered in shrink tubing, and I put it into a piece of split wire-loom. It looks like any other wiring under the truck.

 

I would also put a diode in the wire from the upfitter relay to prevent back feed to the upfitter if you shift into reverse while you have the lights turned on manually. It probably won't hurt anything without it, but diodes are cheap and easy. :-)

(and make sure that tailgater isn't an unmarked cop car. He might not let you off even if he was tailgating you...)

 

Can you put two in parallel or choose a bigger one to avoid this?

 

Diodes in parallel are no different than a single diode. No matter how many you have in parallel, the total voltage drop is 0.6 volts. They are a semi-conductor - and respond differently than a resistor. Even if you use a big Diode that can carry a lot of current - they all drop 0.6V across their P-N junction.

If you put diodes in series, then the voltage drops add up; 0.6 volts each.

 

If you are worried about voltage drop across the diode you should use that circuit to power a relay and bring fresh, clean power to the relay for the operation of the lights or whatever you are attempting to operate.

 

That voltage drop is insignificant. I was just curious.

 

Great information posted. Is it possible to wire in reverse aux lights to an up-fitter switch so that they are:
always off (so not to put out too much light while camping or close to an object)
On in reverse
Always on (when needing to light up a camping spot)

in thinking out loud I think that it would have to be set up with 2 up-fitter switches to accomplish this since none of the up-fitters are dual pole. So switch one on works with reversem switch 2 is aways on and all switch one and two off is always off. Is there another way to do this?

 

hollapm - haven't done it myself, but you're correct - need 2 upfitters.