Originally Posted by pizzaguy

Just keep in mind (and I'm speaking with 30 years in electronic troubleshooting) that the weirdest and most confusing symptoms can be caused by a loose ground wire connection or too low or too high voltage - simple things that are often easy to fix, but hard to isolate.

Your car sounds like it has several modules damaged - and that is unlikely. That is why I think the CAN bus is messed up or power being fed to a module or modules may be bad.

Taking the cover off that box next to the battery is easy, and pulling the floor mat up is not too hard, but getting to the module in the trunk is (I think) a bit frustrating.

Just for grins and giggles, follow the battery ground cable to it's end at the chassis and make sure it's clean and tight. Anywhere you go in the car, notice the tightness and cleanliness of wires and lugs on the various ground bolts. I have had (in other cars) ground nuts work loose causing all sorts of troubles.