jumpstarting with multiple jumpstart cables/genius boost
Thread Starter
Instructor
Joined: May 2018
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jumpstarting with multiple jumpstart cables/genius boost
Hi,
I had read (before) that when jumpstarting a corvette, you need to actually connect the negative jump start to the body of the car (not the -ve terminal of the battery, otherwise you could do damange to the ECM/etc).
So whenever I've had to jumpstart the car - I do that (and have a big massive battery charger).
I also have one of those nice compact 'NOCO genius booster' packs (GB40), but the cables are too short to do that. So I am wondering - can I just take regular jump start cables to 'extend' the -ve terminal to make a contact point on the car body to jump start it?
Or no? Or is there anything I should be aware of (I'm aware to make sure the 'connected' +ve ends would not touch the car body)...
Thanks!
I had read (before) that when jumpstarting a corvette, you need to actually connect the negative jump start to the body of the car (not the -ve terminal of the battery, otherwise you could do damange to the ECM/etc).
So whenever I've had to jumpstart the car - I do that (and have a big massive battery charger).
I also have one of those nice compact 'NOCO genius booster' packs (GB40), but the cables are too short to do that. So I am wondering - can I just take regular jump start cables to 'extend' the -ve terminal to make a contact point on the car body to jump start it?
Or no? Or is there anything I should be aware of (I'm aware to make sure the 'connected' +ve ends would not touch the car body)...
Thanks!
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While I'm aware of not using the negative cable to the battery, I don't think I ever heard of damage to the car's computer if you use the negative battery terminal. I was thinking the purpose of not using the negative battery terminal was not to create a spark near the battery as it could cause an explosion. Though, I never heard of this happing either. I can say I've jumped my C5 many times just using the battery terminals and have not had a problem. Is it the right thing to do 
Le Mans Master
Joined: Sep 2021
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From: WI
There is no difference between the negative terminal and any grounding point on the frame or otherwise. All grounds go to negative terminal. The reason the negative terminal was avoided was in case the battery was leaking enough hydrogen sulfide and the contact spark ignited that gas.
I don't see how enough gas could be released to get even close to ignitable concentration in the air, and moving a few inches away to a different grounding point is a feel good measure at best. "I ground on the frame and my car has never blown up therefore it works" kind of deal.
I wouldn't hesitate in the least bit to go with all terminals.
That being said, if you blow up your car, please let us know.
I don't see how enough gas could be released to get even close to ignitable concentration in the air, and moving a few inches away to a different grounding point is a feel good measure at best. "I ground on the frame and my car has never blown up therefore it works" kind of deal.
I wouldn't hesitate in the least bit to go with all terminals.
That being said, if you blow up your car, please let us know.
Banned Scam/Spammer
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From: Indiana Cornfield
Get yourself one of these and throw it in the car somewhere. I equipped ALL my vehicles with one. This will start a stone cold dead battery. I did it to a truck that sat in FLA for 6 mths. Fired right up after no lights, etc.
https://www.ebay.com/itm/29439057427...kAAOSwah9hPE~M
https://www.ebay.com/itm/29439057427...kAAOSwah9hPE~M
Le Mans Master
Joined: Sep 2021
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From: WI
I have an Autowit SuperCap 2 batteryless jump starter, and had worked just as advertised when my VW got low from sitting too long in winter. No worries about keeping a charged jump starter. Won't help a dead dead battery, though you've got more serious problems at that point.
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Le Mans Master
Joined: Sep 2021
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From: WI
Jury rigging ground to extend it with a jumper cable frankly introduces more risk than just hooking up to the negative terminal.
And actually you're talking about a jump starter, not hooking up to another car. None of your connections will be live as you're hooking the thing up. There will be no spark. So you're applying an irrelevant precaution to the situation.
You hook up your jump starter, then turn it on. It is completely different from jumping via another car whose battery is always live.
And actually you're talking about a jump starter, not hooking up to another car. None of your connections will be live as you're hooking the thing up. There will be no spark. So you're applying an irrelevant precaution to the situation.
You hook up your jump starter, then turn it on. It is completely different from jumping via another car whose battery is always live.
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I have had to jump start my car with a GB Genius, directly to the battery poles. The car did not explode .... yet. 
electrically, as written by others before me, there is no difference.... the ground is the ground, on the battery or on the frame....and the shortest to the starter is on the battery.
I will continue to jump start on the battery if/when needed.
my 2 cents.
TCFS
electrically, as written by others before me, there is no difference.... the ground is the ground, on the battery or on the frame....and the shortest to the starter is on the battery.
I will continue to jump start on the battery if/when needed.
my 2 cents.
TCFS
Burning Brakes
Joined: Mar 2020
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From: KY
Today's sealed batteries do mitigate the possibility of explosion while jumping and using the negative post of the battery but when batteries had caps that you refilled I had a good friend that had one blow up in his face. Was not pretty. Good looking guy scarred for life.
Last edited by Autoeng; Oct 12, 2021 at 07:51 AM.