arming on lock with door open

I was thinking about this today and was wondering if it is possible or if the timing would be off. With vehicles that are "factory arm on lock with door open", could you connect the factory alarm arm wire off the r/s to the door pin so that on lock, the vehicle would sense the door open and arm, or is the timing too close together for this method to work?Kenny

Owner / Technician

KKD Garage LLC

Albany, NY 12205

It should work fine, but to take the guesswork out of it OR if the timing isn't working with just the arm wire, I usually split the lock wire (diode isolated) and connect one end to the factory lock wire and the other end to the door trigger wire. If it's a newer Ford/Mazda with the N.C. door trigger wires, I will put the other end of the diode isolated lock wire to Pin 85 of the relay setup. Although, the arm wire is probably better since it will pulse the door trigger for R.A.P. once the RS shuts off.