Sorry if I have missed it but do you know if they ever tried to replace the battery?
Sounds like either a bad battery or a short to me.
Could be as easy as torn/damaged insulation from a wire causing a short. The problem is finding the wire....
I had a mouse one time living in a car over the...
Replaced the stock floor mats today with custom made mats.
Double stitching with same color thread to match the seats stitching in color and style.
Had them embroidered also.
I don´t know what the US manual states but in the Swedish one it is stated that you can run up to E25 safely.
I doubt the internal of the engine is different in the US but I could be wrong.