Problem with the battery on Nissan Altima?
I'd like to know if anyone has encountered this issue before or have heard of it before (and/or knows a solution). My sister has a very low mileage 2010 Nissan Altima that she bought used in 2011. It was always parked outside but has been working fine while she was in the US (in the midwest, where it gets very cold in the winter). She has since moved to Canada, and had to take it to a dealer to enable DRL on the car in order to be able to get it registered in Canada. Since moving to Canada, the car has been parked in an underground parking where it is never cold.
It's been about 2 years now that the car wouldn't start if it sits without being driven/started for extended periods of time (by extended, I mean 6 months, 3 months, and 3 weeks!). It barely cranks but doesn't start. I had to jump-start her car twice so she could take it to the dealer: first, they changed the car battery and the battery of the key fob; next, they just recharged the battery. The dealership says the (new) battery is fine and that she should always make sure that the car doesn't sit in the parking for extended periods of time. I find it absolutely absurd that parking your car for a month is considered "extended"!
I know that the underground parking's walls are washed with high-pressure water every couple of months. I noticed that every time my sister's car doesn't start, it is completely covered, bumper to bumper, with a thick layer of dust which came down with the water; my guess is that somehow water goes into some parts and causes a short circuit, OR there is a short circuit somewhere, OR something doesn't turn off, either of which would drain the batter.
I have searched online, and there are numerous reports of Altimas eating through batteries, but afaik, no one seems to have found a solution for this. Does any of you have dealt with this issue before? Any tips would be really appreciated.