3 cold-weather questions about car batteries and wipers

Q. Why does my car battery keep dying?

A. Cold weather may not be the only thing killing your battery. We’ve received letters from several readers complaining that their car battery has been going dead for no apparent reason, even with the car sitting in a garage.

One frustrated Honda Fit owner voices a common sentiment: “It keeps depleting and needing to be recharged. This is a defect and not my problem.”

Once you’ve ruled out the common problems such as a weak or faulty alternator, slipping drive belts, and loose or corroded battery terminals, it probably is your problem. All batteries lose strength over time, including new ones sitting on a shelf in the store. If you’re an urban dweller who occasionally drives only short distances with the lights and other accessories on, or someone who doesn’t regularly drive your car, that will accelerate the process.

Also, new cars use more juice just sitting still than older models did. That’s because everything from antitheft systems to standby electronic features draw juice even when the car is turned off.

The best bet is to start your car every few days and go for a spin of not less than 15 minutes—not only for the sake of the battery but also for various other components. You might consider investing in a trickle charger to keep the battery charged and ready to go.

Q. How often should I replace my car’s wiper blades?

A. The short answer is, more often than you might think. Our tests have found that even the best-performing wiper blades start to lose their effectiveness in as little as six months. Streaks or missed expanses of glass are sure signs that the blades are ready for retirement.

One way to stretch the life of wiper blades is to clean the rubber edge periodically with a paper towel and glass cleaner. If that doesn’t do the trick, treat yourself to new blades. We recommend replacing them as often as twice per year. The good news is that most are easy to install, and some stores, such as Advance Auto Parts, will perform the replacement work free of charge.

Q. Why won’t my car start when the temperature drops?

A. If your car is reluctant to start on cold mornings, you’re not alone. With the onset of winter temperatures, owners of a wide variety of vehicles find that their engine won’t turn over, or that it runs roughly when first fired up. Those aren’t old clunkers we’re talking about; the list includes models that are practically new.

Depending on the make and model, a frozen relay or valve may be the culprit. Batteries also lose significant capacity as the temperature drops, compounded by thickening motor oil that puts a greater load on the battery. But that shouldn’t be happening; manufacturers test cars to withstand conditions at the Arctic Circle. Odds are you’re living well below the permafrost line.

The good news is that some manufacturers have quietly been issuing Technical Service Bulletins (TSBs) to address those non-starters, which means you may be able to get your car fixed free. If one of the vehicles listed in the chart below has left you out in the cold, it may be time for a visit to the dealer. Even if yours has been starting up fine so far, have it examined before you get stuck. (TSB summaries are available on the car model pages.)

See our complete guide to winter driving.

This artlcle also appeared in the December 2014 issue of Consumer Reports magazine.

More from Consumer Reports:
The 10 most reliable cars under $25,000
5 best used cars for teen drivers
Best cars for comfort

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