I'm wanting to wire up a switch to enable my box lights to come on whenever I open the Tgate, and shut off when I close it. The switch that is back there appears to be a momentary switch to ground, in parallel with in cab switch. My mind is telling me I need a off/on/off switch to make, then break when I open the gate, then make, and break when I close the gate. I'm afraid to use just a simple single pole switch, since it would be closed when gate is open, and have power being fed to ground continuously, not sure that's a good idea. Any suggestions?
I'll tell ya, I've wired many houses/barns/garages, but this stuff in the truck ain't the same with the BCM's and other acronyms that do magic things.

 

I see why no one wants to get involved, I wrote all that like a raving lunatic. All I'm wanting to do is get the lights to turn on when I open, and turn off when I close the Tgate. Through screwing around with the switch in the rear of the bed today, using my VOM, I saw where when pushing that OEM switch, it would make contact, and break contact even if I held the switch down. Would a regular momentary switch do the same thing? Thinking either a plunger type, or magnetic switch. Normally open?

 

Would need to see a wiring diagram of your truck to be sure, it's most likely a solid state switch as it behaves as you describe. Knowing how the lights are wired in a 2nd normally open switch might be used to complete the circuit with a diode to prevent feedback to what ever receives the signal (BCM most likely) with gate open as you seek.

With the highly complex electronics involved in today's vehicles, I wouldn't want to offer any advice without further study. Got a wiring diagram?

 

That's why I'm afraid to just throw a switch in there, I do know the in cab switch, and the one in the box, are parallel wired. I'll see if I can find a drawing.

 

Found one. Both switches look like normally open.

 

Well you found part of one lol. Need to see the whole thing.

 

Two thoughts you could wire in a third momentary normally open switch, or if it were me I would disconnect the wires from the bed switch, make that a dummy switch and use the wires off that switch to a new one. I tried searching for a plunger type waterproof/dust proof switch I would trust but haven't found one yet.

Sounds like a fun project though may have to copy this.

 

Hood switch would be ideal but knowing how to connect it in circuit without frying something is entirely different.

 

Agreed and good call on the hood switch didn't think to look at those. Also thanks for making me want to put in a under hood light now as well.

 

Ahhhh, I'm still looking for a drawing.