One item just came to mind after a recent discussion with Daves89 about the black car that my older son now has. This car had an unfortunate electrical incident too, prior to Dave owning the car. It was either a battery short or the alternator was shorted to ground, that doesn't matter specifically, but #1 son discovered this last summer while trying to trace a somewhat similar issue to the above. He found a fuse, that doesn't appear blown, but resistance is very high, so it acts as if blown. Photo attached. The point being, pull fuses involved and look at them and replace as suggested above if there is any suspicion.