battery question

[Pajero]

My pajero would not start after work today...as it was -15 the battery seemed really weak right from the get go...so i hooked up the jumper cables from one battery to the other under my hood and it started fine....I thought both batterys were for starting...so why would it make a big difference to hook them together with jumper cables??

I had them tested a week ago and the battery closest to the firewall was pretty weak the guy said but the other one was fine, both were replaced two years ago....

Any Ideas? oh and if I replace the weak battery with a different brand does it matter?

Joe

[thedjjack]

either they have been isolated from each other..

More likely poor connections at the posts...clean the post

[FalcoColumbarius]

either they have been isolated from each other..

More likely poor connections at the posts...clean the post

X2, clean all your terminals and cable ends with a wire brush or emery cloth.
I've just been through this ~ a substantial change in the weather can create a condensation barrier, and not necessarily one that is obvious.

Falco.