Hello all,

New to the site with a question I haven't been able to find searching.

I have a '22 2500 WT diesel 4x long bed crew cab. The tailgate is replaced with a lift gate. The upfitters also put in a backup alarm. I want to put in a kill switch on the alarm for when I'm backing into my driveway late at night, trying to be a good neighbor. I'm wanting to do this cleanly with minimal effort and disassembly if the dash.

Since the factory gate is removed, I have an extra button (tailgate release) on the dash and I would like to repurpose this to activate a relay to silence the alarm.

My first thought is if this is simply a momentary switch giving a 12v pulse it could hit a form c relay sealing itself in while opening the hot to the alarm.

The alarm would be on the NC contact, the sealin circuit on the no.

If I put it in reverse without pushing the tailgate release then the alarm works as designed. If after putting it in reverse I hit the button it silences the alarm until I take it out of reverse which will release the sealin, resetting the circuit to operate as normal next time.

It looks like the upfitters tapped an existing green wire with a black, ran it to the cab, then brought a red back to the alarm.

Would this work or is there something about the way the tailgate release works that would keep this from working or potentially damage some electronics?

If this was on my old 70s truck it would be easy, but with all of the electronics all over the new trucks I'm concerned about the back feed I'm causing between the 12 power to the alarm and the tailgate latch switch circuit. Maybe a diode to isolate?

Is there a good resource for wiring diagrams? I've searched but most that I've found are hard to determine which specific diagram goes to my truck.