When a jumpstart goes wrong? Safety Question

Neighbor tried jumping my wife’s ‘06 Nissan Altima, we left it for 10 minutes and came back and the cables had melted through the headlight of both cars and some of the bumper. I wasn’t there but thankfully they stopped their car and were able to disconnect the cables without incident. We noticed after there had been mice living in around her engine from the mouse poop, minimum the last two weeks. What causes jumper cables to do this? Something a rodent may have chewed? Definitely an issue with my wife’s car. Our poor neighbors have a newish midsized suv. My wife has also had constant issues starting her car, even with a new battery I got a year or two ago. Anyone seen this before?

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161

u/PoliteCanadian2 Dec 31 '23

What do you mean you left it for 10 mins? Connect, start the dead car, disconnect immediately.

125

u/[deleted] Dec 31 '23

They were both applying their clown makeup in that 10 minutes.

7

u/Party_Koka Dec 31 '23

🤣

19

u/Tylerdirtyn Dec 31 '23

99% of the time the dead battery needs to be charged by the donor alternator for a few minutes to start...

14

u/YOOOOOOOOOOT Dec 31 '23

For maybe 30 seconds, there is no reason to walk away whilst jumping a car

3

u/somerandomdude419 Jan 01 '24

I’ve had some batteries take 2-5 minutes but not a Nissan Altima lol

3

u/YOOOOOOOOOOT Jan 01 '24

Still not enough time to warrent walking away

1

u/somerandomdude419 Jan 01 '24

True that, I would always watch the cables and the car running. Thats crazy they even make jumper cables this weak, not insulated well enough

1

u/Tylerdirtyn Jan 01 '24

For 30 seconds? Takes 5 minutes to jump my 07 Civic with the 2017 Accord and 4 gauge cables. I don't just talk on things I don't know about. You guys jumping stuff instantly must have HO alternators and huge batteries, that's not standard equipment.

2

u/spooniemclovin Jan 01 '24

r/nissandrivers

7

u/ChinoManda Dec 31 '23

No, if the battery is fully empty you can leave it on for charging a bit

4

u/Mutated__Donkey Dec 31 '23

That’s what the alternator is for. You start the car with the jumper cables than disconnect.

33

u/Minute-Cod5887 Dec 31 '23

Sometimes jumping doesn't even work, you need to let the battery charge a bit. Happens quite frequently up north where I live. Never had any problems.

8

u/DunceMemes Dec 31 '23

Even in the coldest weather, I've never had to wait more than like a minute to be able to start a dead battery. Waiting 10 minutes sounds like a clear indicator that the neighbor only sorta knew what he was doing and definitely had the cables swapped

12

u/emmejm Dec 31 '23

It really does depend on HOW dead the battery is. If this car was sitting long enough for mice to move in, it’s very likely that it required at least five minutes of charge time before starting. If charge time is needed, lower quality cables will charge slower than heavy duty cables

1

u/DunceMemes Dec 31 '23

I suppose the quality of the cables is a big factor here...because isnt it true that if the two cars are connected properly, he recipient car should be essentially using the donor car's battery to start, rather than charging its own battery per se?

5

u/emmejm Dec 31 '23

It only gives a little boost, not the full power of the donor battery

1

u/toastmannn Dec 31 '23

I thought the point of jump starting was just to power the starter so the vehicle starts and the alternator can charge the battery?

2

u/emmejm Jan 01 '24

When you jump a car, you’re not providing power directly to the starter on the dead car. The power from the donor battery boosts the charge in the dead battery. The more dead that battery is, the more charge it needs from the donor battery before it will have enough power to turn over.

1

u/Tylerdirtyn Dec 31 '23

Well you must have 1/0 jumpers and a 250 amp alternator. That's not standard.

1

u/Omgazombie Dec 31 '23

You’re running the car off someone else battery, you could literally connect your jumpers to your cars battery terminals, and your battery could be on the ground, and the car should still start since it’s a direct 12v connection, just like your battery cables.

Does your car have problems starting with your battery connected to its terminals? No? So why would it have trouble with another direct 12v line also connected directly to a battery?

1

u/[deleted] Jan 01 '24

Because that's not how electricity works bud, sure if you took another car battery and put it 2 inches from your dead one and used high guage cable you would get an instant start. However, that's never the case. Taking a battery below 12 v to back up to 12v across a pair of smaller guage jumper wires does not always start the battery within the first 2 minutes.

6

u/ChinoManda Dec 31 '23

But sometimes the battery is too empty for spinning the engine, you have to leave it for some time before starting the car

3

u/thebigaaron Dec 31 '23

10 minutes is a bit excessive, but if the battery is really dead and the Juno leads aren’t making excellent contact, it definitely takes a few minutes to charge up.

1

u/Mitt102486 Dec 31 '23

Shouldn’t do that at full amperage tho

1

u/aLameGuyandhisCat Dec 31 '23

She needed to pay him.