2012 Leaf won't start and all kinds of warning lights

[WBYeats]

Our 2012 Leaf (bought new) with 24K miles, 2-3 bars down, suddenly won't start and several warning lights come on:
Master warning light
Brake system warning light
EV system warning light
Supplemental air bag warning light

The battery light shows full charge. UPDATE: I just realized that if we've ever had the 12-V battery changed, I don't remember. Seems it would have to have been changed after 12 years.

Stepping on the brake and pushing the start button brings up the display but that's all, and it has the warning lights. Interior lights come on but headlights won't. Heated steering wheel, heated seats and AC lights start flashing. Car makes no sound. I left the display on while trying to read the manual inside the car, and soon the whole display started flashing, then went black. Only the start button light remained lit, and with no display I couldn't tell whether I was turning the car on or off. When I got out of the car, it started beeping and flashing "key not detected." But pushing the start button again didn't change anything. And of course we can't shift it into gear because it's not on.

This car has been perfect its entire life, it's my wife's baby, and we've maintained it well. We did have a cold snap and ice storm, but it's in the carport, the temps didn't get below 19ºF, and it's been through this kind of weather before (we're in Oregon). This was the first time we tried to start it since just before the storm.

Does anybody have an idea what's going on? At this point we'd have to have it towed to the dealer. Many thanks in advance.

 

[Stanton]

UPDATE: I just realized that if we've ever had the 12-V battery changed, I don't remember. Seems it would have to have been changed after 12 years.

Seems like you have answered your own question: replace the 12v battery (which should also clear any error codes).

 

[Hotrodskyler]

Your 12v battery under the hood is dead. I had the same problem on my 2018 nissan leaf sl. Change the battery and it will fix your problem

 

[Hotrodskyler]

Its your 12v battery under the hood. Change it and it will fix your problem. My 2018 nissan leaf sl did the same thing.

 

[WBYeats]

I could swear I responded here weeks ago with the solution. Anyway, you guys were right. I found an AGM battery (Duralast) at AutoZone -- exact same size. My battery was so dead they would have had to try to charge it to even measure the charge. It was a super-easy install -- at least it wasn't a 40 pounder. And everything started up instantly, perfectly, no resets necessary. And I've gotta say -- an original battery that lasts 12 years is kind of unbelievable, like a person living to 120.

 

[cornbinder89]

I seen a few that have, but that is the outside limit on an automotive battery.