So today my car battery died, couldn’t even be revived with a jump. I was able to walk to an auto store to get tools and a new battery (damn that mfer was heavier than I expected). I had never had to replace my own car battery before.
I screwed the fastener nuts the wrong way for like 5 minutes, cut my hand, and ultimately accidentally crossed the positive and negative terminals with a wrench that exploded in sparks. I don’t even know what stopped me from being electrocuted but I didn’t feel a thing.
While I’m happy I was able to take care of it myself and will be able to in the future, I also feel like such a dunce for not knowing wtf I was doing and almost shocking myself
In general yes. Replacing a car battery is something you don’t wanna screw up even once.
One time while screwing a battery into a jeep, I started hearing a strange noise/feeling an itch in my hand. It took my like an entire minute to realize that I was touching both battery terminals and what I was feeling was electrocution.
I was once shocked when I touched a spark plug wire on a snowmobile, even though it was isolated and I was wearing thick gloves.
Fortunately, 12 VDC isn’t enough to do any lasting damage and certainly can’t kill you.
(Yes, I know “it’s the current that kills you,” but do the P=IR on average human body resistance and deadly current and you’ll find ~30 VDC is the minimum voltage across the heart that can kill an adult)
When I first started working with electrics, they taught me to keep one hand in my pocket when I’m screwing something into a battery or other electric terminal. It’s a good reflex to develop because it prevents you from mindlessly touching something with your off hand that completes a circuit.
We called it the “One Hand Rule, no not that one”
That and removing all watches, rings, and necklaces are the most important precautions when working with live electricity. But, it’s always best to not work on live electricity wherever possible
“Volts jolt, but mills kill”
??? its really fine.
There are hazards, but most of them really aren’t that bad. 12v isn’t enough to break the skin so its not a shock hazard. if you wreck the battery, which isn’t easy, the worst case is you’re back where you started with a non-running vehicle The only bad thing really is the very rare circumstance where it fails so wrongly that it either explodes (very difficult to have happen) or sprays acid (they’re designed not to do this, though I’ve heard of it happening once in a racing environment).
Put the battery in backwards and now you’ve totaled your car.
I actually managed to do this once. Turns out the car had a fuse SPECIFICALLY to prevent this kind of fuckup. So hats off to the Mazda engineer in the 1990s for including that. Actually, I assume these are fairly common, but it had never occurred to me that such a fuse even existed.
Unfortunately my friends kia did not have that.
They just tapped it and it wasn’t bad enough to completely kill the car, but everything besides the basic functions were toast and it had a bad battery drain. Radio was toast, power windows and locks toast. A/C was intermittent, but it ran and drove. He installed this water tap looking thing and every time he got out of the car he had to turn it off.
Then again this is also Kia who didn’t include an immobilizer as standard until 2021
typically not the case. Reverse polarity protection is common, and many cars are designed such that (if you bought the correct kind of battery), the cables won’t even reach if you put it in backwards