(First post for me) I have a 2012 with 106,000 trouble-free miles. Bought it used from brother in law in 2014 with 40k miles. It's been a great car. The engine light came on and on-star notified me of a battery issue so I took it to the dealer. $450 to diagnose. It's a battery heater issue that will cost an additional $1100 to fix. Two questions here: Is this a reasonable estimate (IDK never had a EV before) and would it be better to have them button it back up without the fix, pay them the $450 and have the battery just completely replaced at this point with a refurbished aftermarket battery? IOW, put the $1100 toward a full battery replacement. I do plan to hang on to the car for at least 5 years.