My guess is the 12V battery has gotten weak or died. 12V is needed to engage the contactors for charging. When you unlock the car and get in, are all the interior lights dim? Do the dash and infotainment screens boot up? Is the EV driveable or does it fail to start?
Actually, it could make a difference. AGM / Lead-acid chemistry becomes slow and sluggish in subzero temperatures. If you already had a weak 12V battery, the cold will reduce your capacity even further, reducing the time you can run 12V accessories while the car is off from tens of minutes to single minutes or even seconds.
A couple solutions depending on how bad it is:
- Start the car with whatever range you have left, jump the car with a booster if you have to. Grab your EVSE and plug it into both ends first before shutting the car down, this will leave no time for the 12V to drain on its own. While running the car, 12V is provided by the high-voltage batteries through an on-board 350V -> 14V power module. Or,
- Get a 12V battery charger or a bench power supply set to 14.8V at any current from 1-15A, lower if the battery is cold. Charging the battery might fix your problem for now, but it would put into question the remaining health of the AGM. How long does it take before the charge cycle finishes? If it only takes an hour or two from dead, that battery is almost completely sulfated and you should get a replacement or go down the battery-reconditioning rabbit hole. I've also heard that the Spark doesn't give time for its 12V to fully charge, and some owners will take steps to fully charge their AGM's with a 3rd party charger at least monthly.
Another thing to check, does the EVSE have a green indicator light, or a red fault light? Are the pins on the J1772 plug or the charge port socket pins clean? A bad contact could lead to failed communication with the charger as well. If the car charges at charging stations but not at home, this could be worth looking into.
Hopefully you can get to the bottom of this issue!