no power when jumping!?

[87-325ic]

so when i take my e30 off ramps, i just dont seem to get enough power to launch high or far enough.. can anyone help me?

just kidding,
So really, when i go to jump start my car, there is absolutely no sign of life when hooked up.
i had been away for a few months, i came home and my parents had been fucking with it.
they tried to jump start it, and hooked the terminals up backwards and tried for a minute or two, then did it the correct way and got nothing.
after about 2 minutes, the cables start heating up to where they will burn you. they are a small gauge cheap set of cables, but i fear something has shorted or messed up from their initial attempt.
Any ideas? any help?

thanks.

[kronus]

I had a very similar problem. At some point a battery gets so fucked up from being discharged that jumping it will not work, as the battery is shorting internally. (thus your cables heating up) Get a replacement battery, and do all your diagnostics with the replacement.

You will need a multimeter for these diagnostics.

First, check to see how much current the car draws when it's off. (Close all the doors and pull the trunk light first, then put an ammeter between the battery ground terminal and the cable) Ideally, this should be 0-50 mA or so. I had 250 mA when I started, which is what cause my batteries to drain and eventually die. If your current draw with the car off is too high, go to the fuse box and start pulling out fuses until the current draw goes down. If your luck is like mine, Fuse 21 will do the trick. The fuse that it goes down on indicates the subcircuit that's causing your battery draw problem.

Also, check the voltage across the battery when the car is on (after you get it started with the new battery). It should be around 13.5V, which indicated that the alternator is charging the battery properly. If it's too low or too high, your alternator is dying/dead.

Good luck, let us know if you need any more tips.

[87-325ic]

thanks very much, i just got home with the new battery, i figured i'd start there,
i also picked up a new multimeter... since all of my tools are not in this town.

after the battery is ruled out, where do i start looking for serious problems?

the main scare is that something got shorted/ melted while the terminals were crossed..

main relay? fuse?

[87-325ic]

fuse 17, (tach, etc) was blown and the battery was the culprit. alt charges fine too.

she runs! e30 love resumes.

thanks for the help.

[StereoInstaller1]

Sweet, man...didn't even pop the main fusable link?

[87-325ic]

i guess not.

at first, the ABS and Battery cluster lights were on, i figured the abs relay got fried, and that the alternator was not charging.

before driving around i saw like 12.3 volts at the battery, and when i got back, both lights were off, and the battery had over 14v so the alt is good for now.

thank the universe that the germans know how to build cars.

[E30Andrew]

main fusable link? can that be popped?