Jump start a car without another car

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FWIW, some cars should NEVER be jump started with other cars. I fried my dash this way. Newer, higher end cars have a rather persnickety computer system. Jumping with other cars will surge and fry the board, leading to expensive-as-hell repairs. Now that I learned the hard way, I recommend everyone carry a portable jumper in their trunk.

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I feel like this isnt as good as reliable jumper cables, wont last nearly as long as cables, will unnecessarily add more batteries and wall warts to landfills, and isnt worth retiring a still useful pair of cables for.

Of course there are going to be applications and situations where this type of system is more beneficial, but the milliions of cables sitting in trunks right now are perfectly adequate.

I say this knowing I am judged as a disgruntled asshole worthy of being mocked by my blog masters, but not clicking the link and expressing my opinion here are my only options. I wish the products sold here could be slightly more thoughtful in regards to its true usefullness.

I come to bb because it offers me glimpses of something deeper than the typical pop consumer level I am usually bombarded with. I feel like bb is better than lazy salesmanship for crap we dont need, and maybe Im not alone.


Wow. Really? Shouldn’t there be a fuse box between the battery and all electronics in the car?


Mind sharing what model of cars shouldnt be jumped with cables?


There’s a very specific way you attach the cables between cars. A lot of people simply attach + to +, and - to -, and have at it. This way will often cause havoc with the receiving car’s electronics. Your owner’s manual should have a diagram for the correct connection, which should include one of the cables grounded to a metal part of the car, such as bodywork. There’s also a proper order in which you attach the cables.


While there has been a noticeable uptick in the adverts - and they are now fixed as the #1 or #2 blog post, it seems - one thing still applies, so don’t begrudge them too much:
The BoingBoing staff has to eat too.

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As ably demonstrated in another recent article, just be sure to get the polarity right…

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So for a mere $100, we can do the same job as 8-AA cells and some duct tape?


Best link I could find on short notice is this one: http://www.mynrma.com.au/get-involved/advocacy/news/why-you-shouldnt-jumpstart-a-modern-car.htm

My mechanic said using another car for a jump is akin to using heart paddles- a quick surge of strong electricity that can save you or kill you. I ended up having to an entirely new dash for my ancient Lexus.

I’m aware of the proper order, but that doesn’t actually protect against the problem.

This is the kind of Power Pack I use. It’s got USB, AC, & DC ports, plus an air compressor and flashlight. Great for camping and emergencies.


I am asking them to be more thoughtful in the products they toss on here, like the ardurino starter set was a great tip. I’m not asking for the impossible and to stop making money. (although, when I see seemingly daily amazon shipments going to bloggers that have the means to live in beach property and drive exotic automobiles, I do begin to wonder where that persons head is at with regards to careful consumption… or, are they making a living or do they need more money just to buy more crap. But there I go shoving my own morals onto someone else.)

Even though websites use readers as a commodity, the websites still have a responsibility to the readers. If readers don’t understand the message and grow tired of a website, then the website loses its commodity. But I’m not even threatening to leave, just asking them to be more careful and I think that is reasonable. Of course I fully understand that trolls are going to troll no matter what they throw up for sale, so maybe slowing my readership really is my only real power? But I’m not going anywhere, and the staff knows that as well.


“And whatever you do: if you get a flat battery, leave the jumper leads in the boot and call the NRMA.”
They are just trying to sell a product.

The CarTalk guys have a well respected national radio broadcast, and are also quite humorous, if you have not heard of them. Here are their thoughts on the matter:

I understand you had a problem with your car and I’m sorry. I’m not discounting your experience, but I do wonder if there is more to the story. Also, I would love to have a couple of minutes with your owners manual- I trust those things first and foremost.


This is correct. You do NOT connect to the black terminal on the battery. On the good car, you connect both, then you ground the bad, then put the positive on the battery.

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As an electrical engineer, I can say that there’s a lot of misinformation out there about what is and is not bad for your car’s electrical system. Not surprising - most mechanics haven’t studied electrical engineering.

The thing that will “fry” a car’s computer is too much voltage. This voltage could come from the donor car’s charging system if it responds to the increased load of the jumped car’s drained battery. Solution? Don’t have the donor car running when you do the jump start. Then the donor car will only be capable of providing the 12V that is in its battery, not the 18V or whatever that the alternator can make.

Sure, you’ve been taught to always have the donor car running when doing a jump start. Why? Its battery is powerful enough to start itself without its own motor running, so its battery is powerful enough to start a different motor without its motor running. The alternator can make only about 100 Amps of current anyway, so it shouldn’t make the difference between it working and not working.

I’m sure someone will have a nice, flamey retort. Go for it.


You mean, a portable power pack capable of giving 100+ amps of current albeit for a short time is NOT truly useful? Many things run on 12V these days, so you can power any car accessory from it, with just a mechanical adapter for the connector. And then there are other power hungry things like 12V soldering irons.

2 Ah is a rather low amount of juice, though.

Also, a nice thing would be also the possibility of going the other way - charging the pack in seconds from a car battery. A low-drop buck converter should be able of doing so, if the cells would support high-current charging and the car battery is charged or the engine is running (or a laptop power supply with its juicy 19 volts is employed or a 24V truck battery is used). There is some noise out there about ultrafast-chargeable batteries using titanium dioxide nanoparticles instead of graphite anodes…

Ok, you can have one, even though I still dont think this would be an important tool for you.

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I am carrying a Chinese 12V 3-cell Li-ion battery with a barrel jack connector (a leftover from another project where they were used as internal power packs), with a modified car USB charger, as my supplementary power unit. 12V pocket source is bloody useful. Before the age of Li-ion, I used to carry a small a-bit-less-than-2-amphours lead acid battery, sometime in late 90’s. It fit in a tactical vest pocket rather neatly.


Ah, Click and Clack! National treasures.

I’m certainly not an engineer, but I did hook up my battery to the letter. So, who knows what went wrong. I’m sure there’s more to the story. Allz I knowz is having a 6 in 1 could have saved me ~$700.

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