MBNA109

So I had to jump start my Mazda today & did a search beforehand just to make sure. Nothing of use that I could find.

The GLK's has a single battery positive post connection under the hood.

I tried to sync the dead Mazda positive to the GLK positive posts & ground both negatives.

It didn't work. Turns out the Mazda's battery was totally dead but obvious question:

1) Can the GLK jump start another car doing just positives connections?

HDRyder9

You will need to connect both positive and negative [ground/earth] connections. You have to complete the "circuit".

MBNA109

Thanks HDRyder9. I thought that could be an issue.

n8nu

Proper way to jump a battery: http://www.carbuyingtips.com/jumpstart.htm

MBNA109

Good site for car buying I've used before esp. the 5 Quick steps to buying a car.

Never knew they had that section - nice & bookmarked! Thanks!

Looks like every1 says to jump the dead battery with + only grounding the - via both + & - connected to the live battery.

Still don't know the science behind that still though.

dlinjuly2009

I recall reading or someone telling me that it's not advisable to use your GLK to jump start another car.

MBNA109

I saw references to that too but nothing conclusive.

rmfnla

I haven't looked but there is probably a remote grounding point somewhere under the hood.

This is done to allow you to make the last connection away from the battery. That way, if completing the circuit creates a spark there is less chance of the battery exploding.

NickTH

" Turns out the Mazda's battery was totally dead "

Then you'll have to wait a few minutes for the dead battery to be re-charged. Just have some patience.
Same thing happened to my BMW, it won't start immediately, then I waited 5 - 6 minutes, it cranked right up.
Now we have a battery charger for overnight trickle charge.

koojo

I had to get my GLK jumped twice due to the defecti e battery ...

MBNA109

Thanks for the update.

The OP was the other way around on the jump.

MKenM

The better question is why was the battery dead on the Mazda? Old, sulfated, or just left something on that drained the battery. You need to find out the cause so it doesn't happen again.

MBNA109

I guess it was time to go: 6 years + 1 month old on 96K miles.

A lot of 2 miles round trip to work.