Stereo Draining Battery?

[dingo382]

So here's my problem, I hope you guys can help me out.

I installed a new system in my car (95 240) about 3 weeks ago, headunit is a pioneer 7400. Everything worked fine for about 2 weeks, when all of a sudden my car starts struggling when i start it up. I'll crank it, and it sllllloooooowwwwwwwlllly fires. So I figure, ok time for a new battery. I get the new battery, problem gone. Four days later, problem comes back. The system is just a deck and 4 new speakers, no amps or subs but its still running off a stock alternator. I double and tripled checked every connection I made, what wires would actually have to be crossed to cause a problem like this? Any kind of help will be appreciated. thanks.

[mrmephistopheles]

i'd check the battery first, unless it's nearly new... If it's older than 2 years, check it.

[dingo382]

Thanks for the tip. Battery was bought brand new at kragens, and when I bought it they were nice enough use a voltometer to show me that it was still full of juice.

So I was going over the wire harness, and noticed that theres a wire for the power antenna, and another wire for a remote turn on. I had the wire for the power antenna connected to the deck's lead for a power amp/auto-antenna relay control. I switched the power antenna wire with the remote turn on wire. Stereo still works, but my power antenna doesnt work anymore because the deck's harness doesn't have any leads for a power antenna. Is it possible that the power antenna was constantly draining because it was connected to the power amp/auto-antenna relay control?

[DuffMan]

Well its not that your stereo is draining the battery when its on (not nearly powerfull enough to do that) but probably draining it when its off.

That or your alternator is nearly dead, but if it was the car would probably die on you at some point while driving.

Try disconnecting the stereo when you turn the car off and see if it still does it. It could even be something else completly unrelated to the stereo. If the stereo is draining the battery you could wire a relay up to it but then you'd loose all your presets when you turned the car off.

[dingo382]

*Bump*

I really appreciate the help, and after switching the power antenna wire/auto-antenna relay the problem is still here. Any other ways that something could be draining my battery? My car is still running fine and theres no sign of dimming on my lights or gauges.

[andrave]

Simple way to find out if its the stereo.
Get a digital multimeter and wire it in series between your negative battery post and your negative battery wire (with the car off!)
set it to measure amps and see what it is reading. a reading of .1 is normal, as thats what you stereo memory lead will use, but if its high, unplug the fuse that goes to the stereo.
You probably have some small short somewhere that is eaten power with the ignition off, so keep pulling fuses till the amps drop back down to normal, and you know what circuit is causing the problem.