Why did you let it sit for so long with out charging?
The answer to that question is in another thread this OP started, here:
Tesla Model 3 PCS replacement [Salvage model 3]
Hello Tesla fans. Recently I bought a salvage Tesla Model 3. The car had a bad PCS and I have replaced it with another one. Sadly the battery won't charge because of "Incompatible software versions" error. Any idea how to sort this?
teslamotorsclub.com