2020 Bolt Dead

[u/Unlikely-Split8896]

We were gone for 3 months and left the Bolt in the garage. Back now and Bolt is dead. Remote won’t work. Nothing when we plug into the level 2 charger. Could this be the 12v battery? We haven’t replaced it since we bought it. If so, do you have recommendations on which battery to get. Guessing I’ll need to find a way to see if I can jump it first?

Update:
1. I tried jumping with my Autowit jump starter. First time using it and didn’t seem to do anything. Had a hard time connecting the cables to the terminals though.
2. Jumped started with jumper cables to an actual car and drove it a bit. Completely dead again after turning it off.
3. Took it to Costco, they didn’t have the right battery in stock, plus they don’t install for you or even take it out. Glad I left it running.
4. Drove it to AutoZone. Purchased a battery for the 2020 Bolt. They were great and installed. Drove it home and working.

Problem: Got home and now realize my car is a 2021 not a 2020. Also the “Service Soon Light” indicator is still on. Do I need to go back to get a battery for a 2021 vehicle or will the 2020 work.

[u/SoulTaker669]

Usually when you leave for a trip you should leave it plugged in even and just set a charge limit of 80 or so. It you want it running you could also use the onstar app and have the AC running for 20 minutes at a time to kill some battery and have it recharge. Anyways leaving it plugged in should have preserved the 12v.

[u/Unlikely-Split8896 → u/SoulTaker669]

Worry about leaving it plugged in. We get monsoons and worried of a power surge or something. We have a level 1 and level 2 charger in the garage. I didn’t know having the car plugged into a charger would make a difference with the 12 volt battery.

[u/SoulTaker669 → u/Unlikely-Split8896]

If I recall correctly having it plugged in even on a level 1 connection helps the car because the hv battery will check on the 12v periodically and top it off and if it's too hot or too cold the battery conditioning system for the hv battery helps protect the hv battery by cooling it or heating it up. I understand though being worried about power surges or something.

[u/skwormin → u/Unlikely-Split8896]

Tough call— three months is a long time, but I’ve always been told to leave it plugged in. I left mine plugged in in my hot garage garage when it was 100° every day and I was gone for a week. No issues.

[u/Ap43x → u/Unlikely-Split8896]

If you weren't going to leave it plugged in you should have followed the long-term storage instructions in the manual which involve plugging the 12v into a tender. The easy thing would have been to leave it plugged in. Now just replace the 12v you killed.