Finally found a cheap trick for checking alternator health that works

I was messing around with my old Corolla last weekend because the headlights kept dimming at stoplights. I was about to shell out for a fancy multimeter from AutoZone when I saw this tip on a forum from some guy in Texas. He said just start the car and disconnect the negative battery terminal, if the engine keeps running your alternator is fine. I tried it and my heart was pounding, but the car kept running like a champ. Saved me like $40 on a diagnostic tool I didn't really need. Anyone else have a garage hack like that? Curious if there are more ways to test parts without buying gear first.

2 comments

2 Comments

victor_perry9013d ago

My buddy tried that exact trick on his old Ford Ranger and it backfired pretty good. He disconnected the negative terminal and the truck died instantly, plus he dropped the terminal clamp into the engine bay and it landed on something that sparked. Took him an hour to find where it landed and he had to get a jump start after that. So take that garage hack with a big grain of salt, your mileage may really vary depending on the car. In his case, the alternator was actually fine, the battery was just super old and couldn't hold a charge anymore.

amy_murphy1513d ago

That one spark sounds like it was just bad luck honestly, and it's pretty rare for something like that to hit a live wire in most modern engine bays. I've seen people do that test on all sorts of cars and the worst that happens is the car stalls out and you just clip it back on. @victor_perry90 your buddy's story is a cautionary tale, but I wouldn't call it a reason to avoid the whole method.