last thing I forgot to add to my reply, if your alarm goes off when the door trunk or hood is opened you have a negative trigger, that is the same trigger you'll need for your sensor to be tied into. what this does is when the line has 12 volts going to it and will not trip until it is grounded. Which is how the alarm triggers itself and starts to sound off. The door pins, hood pin and trunk work off the same way when the pin is fully extended out it makes contact with the 12 volts and triggers the alarm. I don't know if you can tie iinto that same Negative trigger that u use for your doors and hood but just thought I'd pass on the info for you.....