Turning off headlights won’t save alternator
Dear Car Talk:
We had a new neighbor move into our neighborhood and homeowners association a couple of years ago. We all have our eccentricities, but this guy has a really odd habit, and I’m hoping you can help answer a question about it. This neighbor seems to believe that by turning off his headlights for the drive down the quarter-mile cul-de-sac to his house, he is saving his alternator and therefore prolonging its life. Is that anywhere near the truth? Never mind the several accidents he’s almost caused because we can’t see his car, the pedestrians and/or pets and/or children that could be run over; does he really save his alternator by doing this? I’d like to ask him why, if it’s such a savings, doesn’t he turn them off in town? Why wait until he’s in a neighborhood with only a couple of streetlights and it’s hard to see, where he could really cause some damage? We’ve tried talking to him. We’ve consulted a lawyer. We’ve tried talking to the local sheriff’s office, but they can help only if they are there when it happens. Unfortunately, although he turns off his lights like clockwork, his comings and goings vary, so there’s no way to predict when he’s going to be driving home. This gentleman is adamant that he’s saving his alternator, and it’s important enough to him that he is willing to break the law to do it. Maybe if a car expert steps in (that’s you, by the way), he will hear the truth. I fully intend to send him your answer. What are your thoughts? — Jane
Wow. Humans are an interesting species.
This guy’s a zealot, Jane. It’s hard to reason with zealots, but you should try one more time. He’s not saving his alternator. Even though the alternator is not powering the headlights during those few blocks, it’s still running. Headlights or not, the alternator is always making electricity to fire the spark plugs and recharge the battery. Not to mention running the fan, the heater, the windshield wipers, the radio, the heated seats or whatever else he’s using.
So, if he’s driving the car, he’s using the alternator. That means the alternator bearings are spinning and the diode bridge is working. Those are the parts that wear out and cause alternators to fail.
So he’s nuts, Jane. But you already knew that. The question is how to get him to stop this dangerous, and unnecessary, behavior.
If reason fails, I think the answer probably lies in the very first sentence of your letter: You’re part of a homeowners association. I would imagine that HOAs have pretty broad leeway in adopting their own rules and regulations. I mean, HOAs can stop people from smoking on their grounds, they can ban loud music or leaf blowers, they can keep you from painting your house purple. I’m guessing they also can require headlights at night. So the HOA should consult a lawyer and find out.
If you’re allowed to set safety rules for the association, propose a mandatory headlight-use-at-night bylaw with a fine for noncompliance, then put it to a vote. Let the vote be 39-1 in favor.
Then all you need is for a couple of homeowners to buy Nest HD motion-sensor outdoor cameras with night vision for a couple of hundred bucks each, put ’em on your front porches, and wait for the video proof to roll in.
I mean, that sounds aggressive. And you want to avoid a fight with people you live among, if at all possible. But if you’re really worried about your kids getting run over by this knucklehead, then you may have to use the greater common sense of the community to coerce him into more socially acceptable behavior.
And imposing a fine is certainly kinder than puncturing his tires every few weeks by leaving a two-by-four with nails sticking out of it in the darkest part of the road and then telling him he would have seen it if he’d had his headlights on. Which — my lawyer wants me to point out — is not something I’m recommending.
So try reasoning with him one more time. The electrical load from the headlights is an insignificant addition to what the alternator is doing anyway. If he realizes that the effect on his alternator is minimal and the effect on his lifestyle will be maximal, maybe a light bulb will go on for him. Preferably two.