2000 Malibu, Sidewinder 6500esp, DEI 555L

Ok, after some more digging I was able to find the PURPLE / white wire. Next to that wire was the white one that I believe KarTuneMan was referring to. I probed both of them and this is what I found: PURPLE / white: idled at about 2.2VAC. When the engine was reved, it DECREASED in voltage. white: idled at around 2VAC. When the engine was reved, it INCREASED in voltage. So now, I'm wondering which to use. Does the wiring database need to be updated?

11. Ok, I read through the shock sensor mounting link thepencil provided and decided to mount directly to the frame. I found a good spot for it, but my sensor doesn't have screw holes and I am unable to use twist ties in this location. I was thinking of using 3M mounting adhesive, but since those are pads, I wasn't sure if they would absorb too much vibration. The other alternative I was thinking would be carpet tape, but I don't know if that will have the longevity of the mounting adhesive. Sorry to keep adding posts to this topic, but I can't find a way to edit messages after they have been posted.

"thepencil, I thought the neutral safety wire was required so that the remote start won't start the car if it is in gear. Otherwise, how will it know? Lastly, anyone have any ideas on the second ignition wire?" You won't need it for your car. How to test your wire 101. IGNITION This wire will test with the key switch in the run AND start position, but never in the accessory position. SECOND IGNITION Second ignition will test one of two ways. It will test with the key switch in run position only, or will test just like main ignition. Like main ignition, it will never show power in the accessory position. If the second ignition shows power only in the run position then the accessory output of a remote start device may be used to power the wire. STARTER Changes state only when the key switch is held in the start position. Interrupting this wire will keep the starter from engaging. Triggering the wire will spin the starter motor. ACCESSORY This wire will test with the key switch in the accessory and run position, but never in the start position. Some cars do not have an accessory wire. SECOND ACCESSORY Test in the same fashion as the main accessory wire.     "white: idled at around 2VAC. When the engine was reved, it INCREASED in voltage." This will be the correct tach wire. "So now, I'm wondering which to use. Does the wiring database need to be updated?" Which is why you need to test the wires first rather than just relying on the information given to you. Not all the car are manufacture in the same plant and same country. This is why you may find a bit of discrepancy in the wiring. "11. Ok, I read through the shock sensor mounting link thepencil provided and decided to mount directly to the frame. I found a good spot for it, but my sensor doesn't have screw holes and I am unable to use twist ties in this location. I was thinking of using 3M mounting adhesive, but since those are pads, I wasn't sure if they would absorb too much vibration. The other alternative I was thinking would be carpet tape, but I don't know if that will have the longevity of the mounting adhesive." You are the installer now so you have to think about it. Get it working for the time being or install it better when it comes off the second around. You don't get a second chance to make the first impression on a paying customer. Zip tied, that wasn't a bad idea you know. At least it won't come off after two weeks when the adhesive start to go.    Be careful whose advice you buy, but be patient with those who supply it.

Ok, the plot thickens.  I went out and used the +12v at the trunk light and used the trunk pin wire I ran as my ground.  When I opened the trunk my dmm showed +12v as expected.  When I closed my trunk, it showed 0v as expected.  So I tested a couple other +12v sources using the trunk pin wire I ran and each source showed a little about .1v when I closed the trunk and 12v when it was open.   So it looks like I am going to see a slight ground on that wire whenever I'm using a +12v source other than what is fed into the bulb.  What should I do?

Another voltage sensitivity issue. Both of the door triggers show a slight ground the doors are closed (around .7VDC) and go to the full 12VDC when they are open. Is the .7VDC going to be enough to trip the alarm?