Education and Communications How to find a parasitic battery drain using test light? How to test for auto battery drain using a dead battery and a test light. Related Posts:EverStart Maxx Lead Acid Marine & RV Battery, Group Size 24DC, has been reviewed.Amazon.com has a group 27 battery weight for deep cycle and electric trolling motor batteries.How long will the internal battery last in a nest thermostat?Can you jump start a totally dead battery?