2003 Galant negative door trigger

Now I have another question.  (This negative trigger thing is kicking my butt).  I have a 2003 Mitsubishi Galant and I want to install that circuit to keep accessory power on until I open my door.  I found the pin switch and it has one wire going to it (Solid Green).  How do I find out if that's the trigger or not?  If it isn't, then where could I check to find it?  I have a dmm (Fluke 77) and a little bit of experience, but I'm totally lost.

Thank you,

USMC6213

If your pin switch only had one wire on it, then thats the wire, and it will be a negative trigger. But, This will trigger a negative pulse when you open the drivers door only, not any of the other doors.  To test connect the red of your meter to the pin switch wire, and connect the black test lead to 12volts  hot. Close the switch and your meter should nothing, or 0. Open the switch and you should get 12volts.(or -12volts.)

Hope this helps.