Elau: Sure, the dealer can check the car for excessive resting current comsumption. On a R129, you need to know what to expect, I am sure the dealer is knowledgeable enough to do this. The test should require a wait of about 10 to 20 minutes to allow all the computers to go into a type of "sleep" mode, so don't expect a immediate response from the dealer. I would say that a cycle trickle charger would work fine to keep the battery up. Be sure to disconnect it before trying to start the car, though, you could fry the charger. Remember about removing the key, that was really stressed when we learned about these cars, some of the computers in the car don't shut down (go to sleep) with the key in the ignition.......Gilly