Q – I read your column about the battery problems with stored cars and I want your opinion of my current nightmare. I have a Cayman S and I store it in the winter time. I bought a battery maintainer and kept the battery on it all winter. This spring, I got in the car and it started fine but after just a few weeks it started to crank more slowly and then would not crank at all. The road service guy came out, jumped the car and it started so I took it right back to the place where I had purchased a Genuine battery a year and a half ago. The service consultant called and told me that the battery had failed due to sulfating. He further said that even though the battery is not very old, the warranty was void since I did not drive my car enough. Now I am really annoyed and $700 later, I have my car back. Have you ever heard of this? –Terry

A – This is a new one on me. I am familiar with sulfating but I am very surprised the problem could be so severe that your battery would be shot just over a winter. I can assure you that hundreds of your local club members store their cars with a battery tender without any damage to the battery. I have to wonder if your charger malfunctioned or if the battery was otherwise defective. I was also not aware that your warranty would be void on the genuine part if you did not drive the car enough.

As far as driving the car with a dead battery, at the risk of sounding like a broken record (if you remember those you might be as old as me), do NOT drive the car if the battery is dead! Tow it in or have the battery charged before you drive it.

But back to the battery issue: When you purchased your battery were you told that the warranty would not apply if you drove your car too little? I would want to know that up front, not a year or so later. I admit ignorance on the topic so I contacted my local parts manager. He informed me that “Genuine batteries are the only brand that we sell which have this limitation. That is why we do not recommend them. We sell two other brands that carry standard warranties without that stipulation. We carry the genuine brand for people who insist on an original battery.” So there you have it. When you know the difference, and when you know the limitations, you can make your own choice next time. If your service provider does not offer you a choice, or does not inform you about the warranty issue, you need to find a new guy.

As far as what to do now, I suggest that the battery be disconnected from the car during storage regardless of brand. Underwriters’ Laboratory-approved battery cut-off switches are an excellent way to do this without ever laying a tool on your car or getting dirty. With the battery disconnected, you can keep the battery maintainer on the battery but it will not have to work as hard since all the parasitic drains will be gone. The down side to shutting off the battery is that you will need to reset your radio stations, the air bag light might come on, and you need to remember to shut it off. I admit, I forget sometimes because I plan to drive it “one last time” before I put mine away and you guessed it…the battery is dead!  MC