Trebest70

Every day this week the truck was dead so would jump it and it would start fine all day. But sitting all night in morning dead again! The other night was just getting home getting off another car and there was a light in truck caught my eye. It's locked up mind you well the light was the climate control unit. So I opened driver door wondering wtf n it goes off as soon as open door. The truck barely turned over like almost dead but started. So after driving truck each time I'd shut it off lock it up and go in house only to find ccu on again. Help what is doing this?