Dear Tom and Ray:

My '86 Dodge Aries K wagon has 22,000 miles on it. I park it in the garage year- round. Because of a disability, I no longer work, so my car sits a lot except for trips to the doctor and shopping. I have a two-year-old battery. This is my second one in four years. My problem is the battery goes dead if I don't use the car every week or week and a half. Should I keep the battery on a charger when I'm not using it, or is there some other solution to my battery problem? -- Sam

Tom: I suspect the problem is that you don't drive enough to ever really charge up the battery, Sam. And when a battery is barely charged, and then sits for a week or two, the voltage can drop below what is necessary to start the engine.

Ray: You may not realize this, but when your car is parked, there are still things that are draining the battery. There's the clock, the radio presets, the gas gauge, the computer. ...

Tom: This car doesn't have a computer. It's an '86!

Ray: All right. The abacus.

Tom: Now it's possible that something is actually wrong -- that something else is draining power, like a glove-box light or trunk light that stays on. So it's worth asking a mechanic to check for that kind of "parasitic" drain. And ask him to test the battery, too, just to make sure it's capable of charging fully and holding its charge.

Ray: Assuming there's nothing obviously wrong, here's what I would do. I'd ask your mechanic to fully charge the battery and install a "quick disconnect" for the positive terminal. That's a toggle switch that allows you to easily turn off the power coming out of the battery. It's very common in marine use. There are two lines that come off the positive terminal on this car, one that goes to the starter and the other that powers everything else. That second one is the one you want to toggle.

Tom: Then, when you know the car is going to sit for a few days or a week, you can disconnect the positive terminal of the battery and fully protect whatever charge you have.

Ray: Of course, you'll lose your radio presets. But you'd probably rather spend 15 seconds finding your favorite station than two hours waiting for a jump-start, right? ***

Auto repairs can be costly! Save money by ordering Tom and Ray's pamphlet "Ten Ways You May Be Ruining Your Car Without Even Knowing It!" To order, send (check or money order) to Ruin, P.O. Box 536475, Orlando, FL 32853-6475. You can also order online.

© 1999 by Tom and Ray Magliozzi and Doug Berman Distributed by King Features Syndicate, Inc.

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