I've turned into an electrical retard

[Eric]

So i used to be able to do troubleshooting like none other, but that was quite a few years ago.

Today i decided to poke around my fuse box to see where my dead battery comes from.

I have massive resistance to fuses 1,9,13,14.



I thought i was a genius for finding the problem so easy... lights are shorted!!!

then i realized that lights use this thing called filaments which are natural resistors. damn.

So how do i find a short? use current draw right?

[StereoInstaller1]

Eric, hte best thing I have found is the old test light trick.

Connect a test light between the negative terminal and the chassis (obviously disconnect the negative terminal) and if it lights up, there is a draw.

Make sure all basic bullshit (glove box light, door lights) are off, then start pulling fuses until the light goes dim...generally, that fuse is the culprit.

GL!
Luke

[TexasIX]

you can hook a multimeter in series between the negative battery cable and the battery. then start pulling fuses until the draw goes away. whatever fuse makes the draw go away is the system you have an issue with.

Dave

[Eric]

you can hook a multimeter in series between the negative battery cable and the battery. then start pulling fuses until the draw goes away. whatever fuse makes the draw go away is the system you have an issue with.

Dave

good idea!

Luke, the funny thing is none of that stuff is there anymore! the car is totally stripped out on the interior.

there is a ton of unecessary wiring in the car at the moment, and I think i took out some of the important stuff. I'd really like to pull it all out and wire the car for only what is necessary to be street legal (lights) but i don't have the balls to do that.

[StereoInstaller1]

You can use a DVM, but a test light is 100X easier and quicker

[TexasIX]

this is true a test light is quicker, i just like the built in circuit protection of a dvom. lol. either way will work.

Dave

[Eric]

so a friend and i teamed up on this today with the advice above. i got the volt meter out. put it on amperage this time, pulled the battery ground and put the volt meter in line between the negative terminal and the negative battery cable.

20.5mA! looks like i have a drain!

we then started pulling fuzes and nothing happened until he pulled #21 which the amp meter immediately dropped to 1.7mA.

Looks like #21 has a buttload of stuff hooked up to it. but only the tachomoeter/fuel economy guage and the injection electronics is still in the car. I've cut or pulled everything else out over the last 2 years.

so my biggest question is what is "injection electronics?" the car still fires up and runs with this fuze missing, but i don't want to ruin something that has actual importance if i don't need to.

does anybody know what part of the injection electronics goes through fuse #21?


On another note, i checked the water level in the battery. out of 6 cells 3 had no water visible in it and 2 had the top of the cell packs visible. oops! I've neglected this battery pretty bad since i've been wanting to get one of those little light weight motorcycle batteries for a while.

[Sean]

I have a drain somewhere as well. When I tested stuff out, I'd remove a fuse and put it back in - only to not have the drain return. Is it not supposed to return then?

[Jean]

20.5 ma is not much.... it might be your cluster / si board pulling it.... since you said you don't have anything else.

Check the ETM, it would have everything listed :)