My parents have a 2010 Chrysler T&C 4.0 that’s struggling to start up. The alternator is new and we can’t determine a parasitic draw. The battery is a bit older, but it doesn’t seem to be a battery issue. Pretty much, without rhyme or reason, there’s times it starts up with no issue, but most times it needs to be jump started to get going again.
You didn't say anything about what troubleshooting has been done. Have you tested the vehicle's circuits to find the source of the parasitic draw?
https://www.youtube.com/watch?v=lRcj1fQcWwU
I did check for voltage and continuity. Nothing seemed out of the ordinary
How to find the source of battery drain:
(don't forget to check the alternator. I've seen them drain batteries too)
https://www.youtube.com/watch?v=KF1gijj03_0
Another thing too is that when we do crank it over and the alternator takes over, if we disconnect the battery, after a minute the car shuts off. Does that still have to do with a draw?
Another thing too is that when we do crank it over and the alternator takes over, if we disconnect the battery, after a minute the car shuts off.
Never disconnect the battery on a modern car when the engine is running. You can damage the electrical system.