It has been -22 for the past few days. I was in hospital for two weeks. Got home yesterday and no start. Instrumentpanel gone crazy started once with a boost, but no more . I need to take quick action. new 800cca battery.
Try removing and cleaning the battery terminals and let it sit for awhile on a charger.
The danger is if the battery has frozen. If so a slow thaw in the house may bring it back.
A dischaged battery can freeze quite easily.