What does it mean when the battery light comes on, at high rpm, on a modern sports car? And then it goes off at all other times? It just comes on, very modestly glowing like mom telling you that you’re driving too fast, at above 3,000 rpm. Surely this, like mom, can be ignored? And what about that voltage indicator gauge? On modern cars it is a ‘smart gauge’, which is like a ‘smart lawyer’ or a ‘smart politician’ or a ‘smart child’. It means that the gauge is a liar and worthless. See, in order to reduce service calls, the car manufactures put in gauges that always read normal, except under the most extreme conditions. For the voltage gauge, this means that it reads just fine unless there is enough voltage to generate nuclear fusion or there is zero voltage, everything in between is considered normal. So we can just ignore that pesky little battery light that comes on at high rpm.

One thing, though, that you should consider about the alternator. It has a direct 20 amp link with Mister battery, so if Missus Alternator decides to get bitchy, she can really cause some pain. So what does it mean when the battery light comes on at high rpm? It means that the alternator is starting to come apart internally and shorting out the electrical system, that’s what it means. It means that you shouldn’t try to take the car out on a 14 lane highway to Bethesda, because old Missus Alternator may just decide to show you who’s the boss.

The first sign of trouble is that the radio turns itself off. Now there is your real voltage gauge, not enough juice to run the radio. Then the AC goes and the windows don’t work, it’s starting to get really hot. Yep, that pesky alternator light is on all the time now, but good old Mister lying son of a bitch Voltage gauge is still smiling happily. Hey, I thought I had more than a smidge of gas left? Truth is, the fuel gauge is a more accurate voltage indicator than the voltage gauge. Now the entire dash panel goes out, that can’t be a good sign, at least the voltage gauge reads zero now, but so do every other gauge, including the speedometer. If this were an airplane, this is where you’d really start to get excited. This is why I really don’t like Airbus, because they use all electronic gauges and flight controls. My little Decathlon has steam gauges that will work right up until a five pound vulture smacks them with enough force to rip a whole in the wing. Steam gauges don’t need no stinkin electricity, course you’ve got 100LL at 25 psi being fed directly to the dash under your lap.

It is truly a compliment to modern engineering that the motor keeps running right up to this point and then heaves with a mighty backfire that shakes the whole frame and slaps the alternator out of her funk. Gauges return and the motor catches. Alas but now Mister Voltage gauge senses that something is wrong and starts going down like an erection that just saw our HHS Director, and everything repeats.

Try driving from Rockville to Frederick at 64 mph. It’s been so long that I have forgotten what it’s like. Even the little old ladies drive by and flip you the bird. Good grief people, I’m doing the speed limit.

Pete

 

Check your belt and belt tensioner.

 

 

the battery light should never be ignored