2001 Infinity QX4 Security system

2001 infinity QX4 3.5 liter engine.
History The car was stranded in a parking lot with a dead battery. It would jump to start, however engine died within 2 minutes of disconnecting the jumper cables. I charged the battery overnight, reinstalled it. Car barely made the 15 minute drive to my house. I replaced the alternator, recharged the battery, then the car started several times with no problem. The car has a engine code for the airbag, and many other items that read low voltages. I cleared all codes. Shortly after the airbag light came back on as I drove the car about 15minutes around the neighborhood, then shut it off when I got home. I then tried restarting, shutting it off about 7 more times. On two occasions when it turned the ignition on, it just made a clunk sound, my initial thoughts were sounds like starter is going bad. I contacted the owner, she said that happens a lot since she bought the car not so long ago. She said its a problem with the security system. I don't know very much about the security system, She said she needed the car right away and picked it up. She took the car home without any problems. She was doing some errands today and when she was leaving the grocery store the car would not start. I went to the car and checked the battery first 12.85 volts. I tried cranking it and it just made the clunk sound that I heard the day before. This time that's all it would do. clunk clunk clunk. every time I tried to start it. I told her I thought it was a starter issue, but need to perform some tests. The starter was to hard to get to to check in the parking lot for voltages to it or even to hit with a hammer for that matter. Scanner Danner often times when looking for direction will do what is easiest. Since she said it had security system problems, We performed a procedure that we found online. Disconnect the neg bat term. touch it to the positive term for one minute. then reconnect the neg cable end. then wait 40 minutes We tried that and now the engine turned over, but it would not start. It turned over very fast like the battery was good and strong. I asked her what she normally does when the security system had issues. She would close all the doors, close all windows, lock and unlock the doors from inside, and then it would normally start. She tried this, now the security light flash about 3 times, once ever second then skipped fourth flash, then return to three flash pattern. We tried several times to start, then it when back to clunk when we tried to start. we repeated the door locking procedure and immediately it would crank over again.
I do have an old Verus D10, its updated to 19.2 I am still learning how to use it.
Im looking for direction. 1. Is it possible that the airbag code can be causing this no start trying to force a person to get it fixed because its a safety issue? She has had this problem for several months that she owned this vehicle.
2. We did also try a reset for the security that was in the owners manual, however it did nothing.
3. The driver side door has bad hinges, but will close all the way, I was wondering if this can have anything to do with security system
4. Why after removing the negative cable end and touching to the positive for one minute, then reconnecting the ground, waiting 40 minutes did it turn over fine, but not start.
5. Is it possible that by touching the disconnected neg cable to the pos cable, that resetting the computer that way could have wiped out key info for the security system, thus making it necessary to reprogram the key?
6. Could it be the key has a battery in it that is bad? There is no key fob, no buttons on the key.
My knowledge is limited, I am on chapter 2 of the scanner danner premium site, I love what I am learning. Thank you Paul for all that your doing!
john kocolowski

Thank you Monde. Active and passive makes sense based on how this vehicle is behaving. I ordered a test ring that gets placed near the key when its inserted in the ignition. It has an led that flashes when it senses a signal from the antenna that's around the ignition key hole. The problem is there is a delay in shipping. It wont arrive until July1. I am going to try and learn how to test that piece that communicates with the key. I will check for power and ground first to see if there is intermittent open or short. If that checks out okay I will try to figure out how to use the lab scope to see if the key checker has communication with the ecm.

today I held my low amp clamp near the ignition when i would attempt to start the vehicle. Sometimes it would indicate some pulses when I would turn the key. Other times it would not. More often it would not. I checked for power and ground to the NATS module located near the key. I did have 2 powers and one ground. I could not seem to get any pulse wave going to the ecm. I unplugged the NATS to see if any corrosion.. It looked clean. I plugged it back in, remounted back to the steering column. Now for some reason the scan tool I have will not communicate with the vehicle, and the security light is no longer flashing. When I checked for powers and ground to NATS, I back probed the connectors. I did not have a wiring diagram, however i did have 2 powers, white/blue stripe wire and orange. Black seemed to be ground. I didn't seem to get and reading from the other wires. I disconnected the negative battery terminal to try and reset the computer. Im hoping when I go back, I will have communication with ecm. Is this common for computer to do something like this to lock out for theft? I don't understand why the security light would not flash or come on any more after unplugging the Nats.
incidently when i first arrived at the car today it would start sometimes, and other times it would not
It has 4 codes stored in the computer when i arrived initially
1. p1130 swirl control solenoid valve function.
2. p1610 NATS malfunction
3. p1614 NATS malfunction
4 Evap system leak (large)
It appears the key is original, very old looking. As far as I can tell It does not come apart for a battery to be replaced.
I don't feel confident I tested the Nats properly since I was unsure what settings to use. I left It on 20volt setting 50ms and 20 ms sweep. it was adequate for checking power and ground, I just don't know if that is a good setting for the pulse i was looking for going to the computer.

Any thoughts on this matter are welcome
thanks in advance,
John

Thank you Monde, I appreciate your guidance in this matter. I did try that procedure yesterday, however it did not seem to have an immediate positive effect. I tried it several times actually in hopes that maybe my timing was a little off. I feel I need to get an accurate wiring diagram to see all things involved. An Interesting fact I did notice on a fuse diagram fuse #16 in the fuse box located behind the pull out tray on the left of the steering wheel has all the same circuits in common with my engine codes. the NATS, Swirl control solenoid, Evap purge solenoid, are all on this fuse. If I am able to get to the car tomorrow I will check the fuse. If that fuse is blown then I will try to determine why it blew. In the mean time Im also going to try to find a good wiring diagram. its so tempting to just change the NATS and the key, however I don't want to be a parts changer. I want to make sure I am seeing the big picture. If the vehicle does get fixed, I want to know why. I will also revisit this procedure that your recommending. I will use a stop watch to make sure my timing is correct. Thank you for the encouragement to do the right thing here.

Thank You very much Monde, I appreciate you!

So today the owner of the car said they changed a fuse and now the car is fixed. Well In my opinion nothing is truly fixed until you know why the fuse blew. Anyways, after the issue with no start remained after I ran tests, the only way to start the car is to bypass the NATS system, my conclusion is the key is not a master key in working order. My reasoning is that I did get a pulse from the NATS coil antenna when I checked it using my low amp clamp, To me that qualifies it as operational. The key has a history of problems, since the person that sold them the vehicle taught them a work around for the security system that tells me this issue was long before I replaced the bad alternator. If it was a master key working properly then the procedure you shared Monde would have worked. One of the qualifications for that procedure is to have a working master key. I thought maybe is was my timing, however, after doing it several times I am of the opinion now that they need to go to someone that can make a master key. Keep in mind there opinion of being fixed may be simply that whatever fuse I blew working on it is now is now a good circuit again. It doesn't necessarily mean they don't have to still do there work around. I wont be surprised if I hear that they get stranded again. Iin that case I will tell them disconnect the battery 30 minutes, then reconnect it and do there work around, and go get a master key made. Thank you for all your help in this matter.