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
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The way you get good at it is by screwing up several times along the way. So, you’re on the way to being good!
Sucking at something is the first step at being kind of good at something
- Jake The Dog
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.
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”
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.
??? 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.
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
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
Comrade, I’m going to assume you’re young. I’m not. But I can tell you as the handiest person I know, I got here because I never stop fucking around with things over the years. Some of my tools have chunks melted out of them from accidentally shorting a car battery. I’ve skinned my knuckles, stabbed, electrocuted, burnt, cut, glued, bumped, and bruised myself, and I expect I’ll do it again some day but hopefully less often. The difference between us is time spent being stubborn about wanting to know how things work and a lot of times needing to save money. Don’t get down on yourself, you changed your battery and that’s more than many people will do.
Keep fiddling with things, you’ll get there. But also, take your time to think through hazards, it makes it a lot easier. Don’t ever rush handy/repair/maintenance work.
not young just sheltered by a ‘middle class’ lifestyle
I was too, now go keep fiddle fucking with things!
GOOD post
what stopped me from being electrocuted but I didn’t feel a thing
Sounds like the electricity was going through the wrench and not your hand. The real dangerous electrocutions are where you touch negative with one hand, positive with another, and the electricity goes across your heart on its way to complete the circuit.
But anyway as a certified handy guy who has done installs and modifications of all kinds professionally all of this has happened to me before too. The only way to get good at it is to do it every day, and most people just aren’t doing that.
I’ve never replaced a car battery and wouldn’t know how to begin, so you’re ahead of me.
I always forget which terminal to start with but luckily they’re at the same height so I can set my wrench down on them while I look it up on yt
I’m assuming this is a joke :P put it anywhere else!
Yes! Though definitely have shocked myself enough to learn I don’t like it lol.
Always disconnect negative first, so that if you accidentally touch any metal parts near the battery while disconnecting the positive terminal, there’s no path for it to complete a circuit. I also have a socket wrench with a rubber-coated handle that I like for working around batteries; I think it was some like $8 Popular Mechanics-branded thing from Walmart that I got like 20 years ago.
There’s a reason insulated hand tools exist! If electricians will spend extra money on it, you know it’s worthwhile lol
You probably know why I wasn’t electrocuted. Was it just cause my feet were touching the ground? I’ve been shocked from an industrial kitchen outlet before and I was touching the ground then.
I was wearing gloves, is that all it was?
You’d basically have to roll around in salt water for 20 minutes to zap yourself on a car battery – they only put out 12-13 volts DC, but there’s a decent amount of amperage behind that (typically 550+ for cranking a gas engine, though I’ve had batteries that were capable of around 1,000). With car batteries, your two main safety concerns are going to be tools or metal parts (e.g., battery retaining brackets) getting extremely hot if they bridge between positive and ground – and the risk of burn injuries that would come along with that – and the battery just outright exploding and flinging hot sulfuric acid everywhere. The second one is rare, since the battery will usually discharge itself before that point.
Hybrid battery packs – the ones typically stashed under the back seat, not the 12V starter/auxiliary battery that you may find under the hood or in the trunk – are a very different beast, and typically put out closer to 48VDC. Those beefy bastards absolutely can kill you.
A car battery doesn’t have enough voltage to even tickle you* so you wouldn’t even know if you zapped yourself. (*assuming you are touching it with y’know your skin and not your tongue or something even sillier)
Buuuuut if you touched any bare metal bits of the car while touching the positive terminal, for example when fastening the bolt on the positive terminal with an uninsulated tool, then you did just zap yourself for however little that matters with a 12v battery. ;)
Oh wow, I didn’t realize that was how little it was. I think the kitchen outlet I shocked myself with was like 200v and that gave me a jump and some tingling. I had no idea car batteries were so little voltage.
The flavor of current also plays a big role too. Car batteries are Direct Current, whereas your 200v outlet was likely Alternating Current. Essentially, even 200v of DC wouldn’t have been as “painful” as the AC you experienced although I’m not playing with either. Part of the danger is the way the alternating current has a tendency to contract your muscles, keeping you in contact with whatever the source is. DC tends just spark, bang, shove you away.
As someone who’s fairly handy (but sucks at lots of other things ofc), the only way you get better is by doing shit and giving yourself a little space to fuck up. I did all kinds of dumb shit to get to where I am, and I’m still not nearly as good at design as my older friend, or as good with cars as my mechanic buddy, or as good at following through on regular maintenance as my neurotypical friends.
I’ve broken off captive nuts internal to the frame of a car, I’ve glued in a stubborn alternator bolt, I’ve tried to cut steel chain with a metal chop saw and wrecked the blade. I’ve seen someone set off a sawstop, I’ve driven a car with no brakes like 30 miles to the nearest town, I’ve vaporized the tips off my multimeter leads by testing the voltage of a 40v battery with them in the 10A position, I’ve bent or broken plenty of (mostly crappy) tools, snapped the heads clean off 100 rusty bolts, rounded them on 50 more. I’ve shocked myself with 120v by working on a powered-on rack mount ethernet switch with it perched on my lap, and then continued to work on it on my lap and did it again. I could go on but the point is everyone does dumb shit sometimes you just live and learn and next time you take on an even bigger project thats even more out of your comfort zone, and the more you do it the better you get.
shit, half of being seen as “handy” is just confidence. If you tell someone “wellll I watched a youtube video and I think I could fix your plumbing issue, probably” people are gonna think “this person doesn’t know shit, nice of them to offer at least but I better get a real plumber”, but if you have absolutely no idea what you’re doing but some blind confidence and you go “oh yeah I could fix that for sure. a plumbers gonna cost you a fortune, why don’t we just do it ourselves?”, you might well get seen as handy even if you just improvise and watch some youtube (not saying blind confidence is the way to go but don’t sell yourself short or assume that “handy” people are all actually competent
Absolutely this on confidence. The first and most essential step is letting yourself be someone who can solve the problem. Next is being careful about it, sure.
Another big part is just careful attention to the parts available, as a huge number of intimidating problems (especially in plumbing) are solved by carefully browsing the catalogue and following up on the leads it offers.
Seconding everything said in this comment, confidence goes far.
I’ve made many mistakes when fixing my own cars so take it from me it happens. There’s this time I put a battery that was too tall in my sister’s car because we didn’t have the money for the proper battery, shit make sparks with the hood as it welded it. I fixed that with some electrical tape insulating it. There’s this most recent mistake where I bored a hole into my new radiator, fixed it with some jb weld few days ago.
Among my friends and family they see me as some sort of mechanic but the sheer volume of fucks ups is pretty massive. Everything runs at least and not being a trained professional I’m doing alright all things considered so be easy on yourself. You didn’t get majorly hurt or anything and you learned some important lessons as long as you don’t do them twice you’re good
Thanks, it was a real ‘necessity is the mother of innovation’ moment cause at first I called like 3 auto shops/roadside assistance places and none of them could help till tomorrow, but I have work in the morning.
So real, I’ve mostly been put in this because we don’t have the money for an actual mechanic. I will say the real curse of being handy is the permanent “temporary” fix. My ac compressor crapped out and made my serpentine belt fall off, I ran a bypass thinking just for now till I fix the ac fixed. That’s been almost 2 years now
The super handy guy at my work was fixing the AC the other day, he tried to explain it to me and I was like I literally have no idea what half those words mean lol
Yeah I forget a lot of the things myself tbh, I only ever find out what they are through watching videos on yt. Makes it easier to find the parts at eh store/online if you have some terminology at hand.
There’s never anything as permanent as a “temporary fix”
Some months back I replaced the alternator in my vehicle. I’ve been working on cars on and off since I was a teenager in the last century, but I mostly get by from watching videos and reading the manuals. So I watch a bunch of videos, get the alternator out of my vehicle, and then proceed to get the new replacement stuck for like 3 hours when trying to put it in. See, all the videos I watched had a hard time of getting their alternator out, so they had to removing a bracing bar. But not me, I twisted it right through the gap, LIKE A PRO!
So when I’m watching these videos and they’re all having no problem getting it back in, I’m pulling my hair out wondering what the heck is happening when it suddenly occurs to me how I screwed myself and that damn the bar needs to come out. lol, what should have been a few hour job took me two days. LIKE A PRO! 
There are less and less things in the world one can even interface with properly, so there’s less and less ways to even be “handy”. You were born in the wrong generation to be handy
born in the wrong generation
Retvrn to turdition
You didn’t feel anything because it’s only 12V. Be happy it wasn’t worse and learn from it!
Yep! There’s a lot of confusion in the public sphere about how electricity works, but you cannot electrocute yourself with a car battery alone - you can touch both contacts at once with your hands and you’ll feel a tiny sensation at worst.
A common myth is “It’s not the voltage that’s dangerous, it’s the current!” and this is the perfect example of why it’s way more complex. Car batteries can deliver lots of current (>40 amps), they have to to run the starter. But at 12v, the resistance of a whole human body means the voltage simply isn’t enough to be dangerous under practically any circumstances (other than maybe pushing the battery against your completely bare chest, for a long time, over your heart, also you’re soaking wet for some reason).
The only danger OP had was if they left the wrench bridging the contacts long enough, then it would have heated up and melted stuff. Bridging the contacts for a fraction of a second and making sparks isn’t actually anywhere near as dangerous as it sounds.
Be happy it wasn’t worse and
Do some fun experiments with your toes
do not play with your toes
We all have our fields of knowledge
Do I know anything about car maintenance? No
Do I know how to cook a variety of delicious and nutritious food? Yes
Yeah I think it’s some “masculinity” brainworms I haven’t rid myself of. I have significant medical knowledge that I use for work, but in day to day life, none of that is remotely useful.
I think there is real value to knowing how to do these things yourself, but feeling shame about not knowing isn’t the right way.
I think it ties into ‘rugged’ individualism, but idk the right way to say it.
I do think there is genuine value in understanding how the things you own function and being able to do some degree of first aide on them but even that can only extend to so many different things. Can’t know everything. You can learn anything though. If you wanna learn car repair, do it, if you don’t. No real need aside from what you’ll need to know just to keep a car (gas goes in gas tank etc)
Being handy isn’t something you just are, it’s a skill built up by not getting killed while trying to be handy. First time I tried to fix a plug socket I forgot to turn off the supply at the fuse box and accidentally shorted the wires. First time I tried to fix a broken headphone wire I just ended up with a mess of wire and solder. First time I tried to replace a light socket I found that the building had been wired before current wire colour standardisation and had to call 3 different people to find out what to do.
Today you made at least 3 avoidable mistakes, but you also successfully changed your car battery, and now if you need to do it again you can avoid those mistakes. You might have injured yourself and your pride, but you tried and you succeeded. You can do it again. You are now handy.
don’t be so hard on yourself, most handy people either learn from someone experienced, or the hard way like you did just nowusually some of both honestly
Glad you didn’t shock yourself and give you a pat on the back for that. I don’t even know my way around cars.
Yeah, I’m gonna chalk that one up to the spectre of communism saving Sulv.
You know more than me. I wish I just stuck to bicycles.
I dunno how people learned 30+ years ago… families passing along info, friends maybe. nobody in my family knows shit, except calling whoever has money and getting them to throw money at poor people until the problem is no longer present.
I left home like about 20 years ago and became curious how to keep my shit from falling apart when some critical machine, appliance or mechanism stopped working and I only had $30 to my name. learned stuff from coworkers, helped them work on their own orojects as an extra pair of hands in exchange for their knowledge. once YouTube became a thing, that’s been real good.
I took some adult Ed. “shop” type of class at a local agriculture school. that was riveting. I still watch YouTube videos for stuff though.
its a real pain to sort through all the AI slop though nowadays.
I think as we settle into imperial decline and become intermittently disconnected from various supply chains… having curiosity and an attitude for tinkering is going to be crucial as communities contract into some kind of neo-mannorialist/resiliency-based whatever the fuck.
my family still doesn’t know shit about fuck and they all seem to refuse to learn anything, treating me like I’m some kind of eccentric throwback for trying to muddle my way through problems and understand mechanisms.
I am perennially disappointed and frustrated by their incurious approach to the world.
I find people who want to at least try to understand a problem and explore their DIY options to be kindred spirits and fast friends.
Tinkering is fun! And if I’m using something with any frequency I’m curious as hell how it works.
Here’s David Lynch showing off his homemade phone holder for filming with an iPhone and talking about pretty much what you said
I found a YouTube link in your comment. Here are links to the same video on alternative frontends that protect your privacy:
I left home like about 20 years ago
Yeah I moved away from family and close friends for the first time like 4 months ago, I spent my entire life within an hour drive.
I think as we settle into imperial decline and become intermittently discinnected from various supply chains, having curiosity and an attitude for tinkering is going to be crucial as things contract into some kind of neo-mannorialist whatever the fuck.
I think that’s partially why I feel bad for not knowing these things. Shit feels like its hitting the fan and at some point you really do need to be able to rely on yourself.
I wouldn’t feel bad, we all start somewhere and it’s a continual, slow process of learning how new things work, repurposing old things to serve new needs, and one is never done learning.
if I had any advice it’s to cultivate patience with yourself as you learn, because if you do you can become exceptionally talented/knowledgeable as you incrementally grow your capacity.
learning in these situations can be extremely frustrating, especially if it doesn’t solve the way you needed it to. but you learn what doesn’t work, what’s a “dead end” and that’s just as important too.
I dunno how people learned 30+ years ago
books, and talking to people, and a slightly more functional school system
