03 Yukon throwing all kinds of warning lights

[1yesfan]

It seems the issues with this truck are making the rounds. All the issues listed so far have not happened for since last noted here but have happened multi times.
The latest is the (it is not aftermarket) alarm (yesterday) went off on it's own 2x. late in the day, we passed it off as one of the remotes got hit. Well 4am it went off again. I was half asleep but recall that it shut off before I could get to a remote or do really anything to stop it.
This does not seem to be a ground issue to me at this point.
New batt and Alt so one would think it is not a power loss of any type. I wonder if I should throw a GM alt on it and a name brand battery in it.

 

[1yesfan]

I read about some PIN in the drivers door for the alarm that could go bad. Maybe a car driving by a door not fully shut is the issue. I don't think so seeing all the electrical issues I see with this darn truck.
This truck has decent miles on it for a 03 (162k), in really good shape but for the drivers seat, zero rust, I wonder if these issues have been around for a time now and the prev owner just dumped it.

 

[1yesfan]

Well I thought I would just stick with this thread since the old girl seems to go wacko time to time. As you can tell I have not posted in the thread in a bit. My son drives this truck. The most recent thing is some time, he says the other day all the door locks flat out stopped working and the when he pulled the key out the radio would stop (as you know it would stay on till the door in opened). He turned off the truck and back on, not fix. He said he disconnected the battery then hooked it back up, the issue then went away.
I feel all these issues are a body control modual issue???? We have checked the ground we could, every thing tight and rust free as the truck is rust free.
Where is the body control modual on these? I assume if I pull one from a junk yard truck it would have top be the save truck, same year, same options, etc? Are these things fixable as far as sending out to a place that repairs these types of things.

 

[06Escalade]

Shotgunning parts can make it more difficult to diagnose if things don't work out and new problems arise. It could be a bum new battery that doesn't hold charge, could be a bum reman alternator. Or an under powered battery/alternator. Track the voltages at diff times. Battery disconnected, reconnected. When you're using the AC. See if there is a trend. Put one of the old ones back. see if the engine lights go away with old battery, new alternator. and vice versa. I have an old Maxima project car. Bad alternator, only charges at 11.5. Slowly, gradually it takes the battery down. And things start happening due to a lack of 12v. Assume you've done all this, just thinking of possibilities.