Captain Tommy,

I can't be any help to you but I've had a 2005 roadster since new and I am having the same problem with batteries. For the last 3 years or so, it is never used. I probably have 100 miles in 3 years, sad! Anyway, I brought the car to the local Dodge dealership last week because I have gone through 4 batteries since January. They told me that there is no extra-ordinary drain on the battery and that they conferred with Chrysler and they agree that the numbers are good. I brought the car home last Friday, used the car on Saturday and Sunday with no issues. On Tuesday, we drove the crossfire for about 25 miles and it was raining, but it was cool so I wasn't using the air. As I was almost home, the windows started to fog so I turned on the defroster. As soon as I did, the battery light came on in the car. I turned it off. When I got home, I turned the car off and went in the house. 5 minutes later I came outside and the lights were still on. As I approached the car, the lights went off. I got in the car to put it in the garage and the battery wasn't sufficient to start the car. I checked with a volt/ohm meter and the battery read 11.56 volts. I had to jump start the car and when I did, the battery read 12.27 volts. I revved the engine and the voltage went to 12.67 and dropped down a little when I stopped revving. To me that says the alternator is working. I haven't done anything else with it since I put it in the garage.
Two things, the first is that I thought it took an inordinate amount of time for the headlights to go out on Sunday morning too. As most of the time the car sits in the garage, I don't think that the lights staying on too long is the battery issue. The other thing is that I installed a battery kill switch so the drain stops, but now I am concerned about having the battery disconnected all the time so I think I will by a battery tender with float sensor. Am I on the right track? BTW, the battery is a 2 week old Interstate.

Any ideas? Thanks!