remote start, 2005 ford f150

Hello gurus of electronics. I hope someone here can help me out. I'm trying to wire an Autostart 2 Way FM remote start system, model AS-2361TW-FM, into a 2005 Ford F150 FX4. The truck is a Supercab with the suicide rear doors, so only the front doors will need to unlock. I seem to be having trouble locating the Lock/Unlock wires, as well as the Arm/Disarm wires. I have looked along the wire harness that runs underneath the driver side running board, but only managed to find the brake wire. I also can't seem to figure out the door trigger (-). So, everything else is installed, but those are my issues. Where can I find the Lock/Unlock and Arm/Disarm wires? Will I be able to keep the priority door unlock? Will the factory door alarm still be able to work? How does one test for a negative trigger? I'm assuming these are the reason the starter isn't fully working, but I'm pretty much experimenting as I'm doing this. Currently, when I hit the start button on the remote the system brings the electricity on, as if it's going to start, it sends a short burst to the starter, but nothing happens. The only other thing, I can think of, is that I haven't programmed the Xpresskit XK04 properly and my bypass isn't working. One last thing, do I need to connect the Keysense wire to anything? Sorry, a lot of questions, thanks for any help.

myinstallguy wrote: Use a DMM for testing any wires. At least a logic probe.

Ok, I got that far. But as far as testing a negative? What should I be looking for or what setting should I be using? That's where I'm having trouble. What change is made that would let the system know that a door has been opened?

I've never seen an F150 with a factory alarm. Not even the Lincoln Navigator has one! unless maybe the Canadian model is different. Doorlock wires: Open driver's door wide. Put your left knee against the door so the wind can't shut it on your hands. Undo the rubber boot in the doorjamb, that carries the wires into the door. Temporarily shove the entire boot inside the driver's door to get it out of your way. Bring your aftermarket wires out there, hook them up, then put the boot back in place. Multimeter: Red wire to constant positive. Set up meter to measure voltage. Touch black meter wire to ground, and observe that you can read (approximately) 12 volts on the meter. Remove black wire from ground, attach to car's doorlock wire, operate doorlock switch, look for 12 volts again.