kittyandgary

My '03 SL55 AMG will be stored for at least a month, and perhaps several months over the winter. I had it stored for a month this past summer and put a battery maintainer on both the starting battery and the one in the trunk - no issues upon returning.

Does anyone have any experience with the effects from disconnecting either or both batteries for extended periods of time - to keep them from discharging when the car is not driven?

Any experience or information would be greatly appreciated.

Gary-

B-tsai

If you already have the trickle charger.. I'd use it.
I imagine you'll have to re-program everything (memory function items/seat/radio codes etc)
Would keys even need reprogramming I'd wonder if it went completely dead.
Don't batteries go stale as well just sitting there?

cal1

+1 I'd stay with the trickle charger as well, but think you only need one on the trunk battery.

I put my SL to bed every winter and have for years. I plug the charger into the harness that I leave connected to the battery all of the time. The car has set as long as six months and fires up like a champ every spring.

One thing i have never done is put fuel stabilizer in the tank. I have never had any issues, but am thinking about putting some in this year.

I do think you would be fine removing both batteries if you chose to. I think all programmable setting would go back to defaults. It seems like the keys would be fine. If you go that route, give the car a few minutes before trying to start after connecting up the batteries. I read somewhere that the ECU will need a minute or so to reboot itself. i also read that disconnected batteries should be trickle charged from time to time so I don't see much advantage to removing them.

Welwynnick

Keep the fuel tank full so you don't get condensation inside due to the tank breathing.

Batteries MUST be kept charged up - never let them go below 12.4V. Might need trickle charging once a month - maybe once a week - whatever's necessary. Keys will be fine.

Lots of warnings go off when you re-connect, but nothing to worry about if the car is kept dry.

I wouldn't disconnect a battery if you don't have to - but it does need to be kept charged.

Nick