joemax1

hey guys! How do you connect the jumper cables to your car? I did what the manual insturcted (connect the (+) to the ohter battery's (+) and the (-) of the other battery to a body ground in my max) but it didnt work. I asked a few friends around and they said to conect the other battery's (-) to my battery's (-), and it worked. Any ideas how this happened? Comments? Thanks

turbodub

Ive heard that if you connect the + to + and the - to - its could fry your CPU cause instead of getting 12v of juice it gets 24v, now im not a mechanic so im not sure if this is true or not. Did you have the - hooked up to a good ground point? That would be the only reason i could think of why it didnt work.

joemax1

I hooked the (-) to metal bolt in the engine bay. how would u know that the CPU is fried?

FrostMaxima

iTrader: (1)

The car wouldn't run haha

joemax1

hahaha...funny! but seriously, my car actually started and is running now. But I was just wondering if I damaged anything by connecting the (-) of both batteries while jump starting. any other VALID comments? thanks guys!

dla

I'm unclear as to what vehicle needed the jumped?

The vehicle with the dead battery has the (-) to frame and this should work! The only thing else is if you did not get good connections at the terminals or find good clean ground (-) on the vehicle to be jumped.

joemax1

I had the (-) of the "booster" battery connected to a metal bolt in the engine bay of my max which needed jumped. But it didnt work. Well I guess I didnt have a good connection on the bolt, i dunno. But when I did (-) to (-) on bothe batteries, it worked. So I went to Advance Auto parts to have my batt checked, which turned to be a bad batt. Bought a brand new batt and the car is working fine. My question is do you guys think it would do harm on the car computer if I had the (-) to (-) connection, even if the car did start? Thanks.

DONS459

I have done it many times on older cars of mine without any problems.

ElementK

Ive also done it numerous times on other cars i have had with no ill effect.

joemax1

and all my friends and even the 2 dealerships I called told me that neg to neg is fine. I was just concerned when another orger mentioned about possibility of "frying" the car computer...

thanks for the inputs guys!

NismoMax80

iTrader: (6)

I also remember "red dead"

Red/Positive on dead car
Red/Positive on live car
Black/Negative live car
Ground/Negative dead car

but due to all the computers, I'd rather call AAA for a guy than use my car...

lightonthehill

Your original hookup was the correct one, except that, either one of the cable-to-battery clamp connections was not well-attached, or, on the final connection, the cable was not adequately attached to the bolt, or the bolt was somehow not grounded to the engine. Getting enough power to start the engine requires a good solid connection at all four points.

One other possible problem (apparently not so in this case) is where the cable is attached to a battery clamp that does not have cood contact with the battery post because of corrosion.

The order in which you made the connections was also correct - Always start by hooking to the positive terminal of the dead battery (the 'positively dead' method), then run that cable to the positive terminal on the live battery.

While still at the live battery, attach the second cable to the negative terminal of the live battery, and the other end of that cable firmly to a grounded bolt, brace, etc in the engine compartment with the dead battery, at a place where no moving belt, fan blade, etc, can touch it.

If you mistakenly make that last connection to the negative terminal of the dead battery, it will do no harm whatsoever to anything electronic. That kind of damage will only be caused by hooking the cable to the wrong terminal (i.e., positive to negative).

The ONLY reason the final connection MUST be made to a bolt/etc on the engine is because this is the connection that completes the circuit, and creates sparks, and the acid fumes from a battery can be very explosive. Many folks (especially in the old days) have been blinded or scarred for life by battery explosions resulting from making that last connection to the battery instead of a bolt safely away from the battery gasses.

We drivers who drove through the 1940s and 1950s can use jumper cables in our sleep. And we did it right. Our friends who did it wrong are long gone.

lightonthehill

I just heard by PM from joemax1. He mentioned that the cars should not touch each other during the jumping procedure (could short out the electrical connection, preventing the starting of the dead car). He is correct. I should have included that detail in the previous post.

Ritz

iTrader: (2)

lightonthehill is right.

only other thing I can think of about the grounding bolt, is that maybe it was painted.. I've put the negative ground on bolts that I could've sworn were fine, but weren't. if you have problems in the future, try a couple different grounding points and make sure all the connections are good.