Thread: Battery is near dead after car sits for over a day?

Ok first off.

Optima red top battery (6 months old) w/clean terminals

Big 3 upgrade + Alt rewire

Cleaned up all grounds

higher output alternator (4 months old)

I do have a aftermarket stereo (pioneer, nothing fancy) and an amp and sub w/capicator
HID's fog and headlight
I also have a radar detector that stays on for 6 hours before it auto turns off. So I usually just leave it plugged in.


Now onto the problem. For the last couple weeks if I let my grand prix sit for more then 1 day without starting it, it either wont start (barely turn over) or struggle to turn over. Mind you its Wisconsin so its getting down into the teens or colder at night.

I don't get it. Its like there is a draw somewhere. So, I grabbed my test light and disconnected the negative battery terminal. I then hooked up the ground on the test light and put the probe on the positive terminal, no light what so ever. Not even a little dim. So I'm guessing there isn't a power draw going on somewhere, otherwise the light would come on.

So why on earth is this happening? I'm currently charging my battery with my charger. The volts were low, but not completely dead.

It makes no sense to me ! New alt, New battery, wiring is all top notch, no draw (at least I think),

Anyone have any suggestions?

Your testing for current incorrectly. Remove the negative terminal and connect the ground to the ground terminal wire and put the probe on the battery's negative post. Or get a DMM, put it on 2A and it will tell you exactly what your draw is.

Originally Posted by KeithGTP03

Your testing for current incorrectly. Remove the negative terminal and connect the ground to the ground terminal wire and put the probe on the battery's negative post. Or get a DMM, put it on 2A and it will tell you exactly what your draw is.

LoL ....OOPS !

I'll try it that way....I post back

SO i hooked the test light up correctly and the light comes on. Its not FULL brightness but its definitely lit up. I pulled every fuse on the car including my amp fuse, all fuses under the glove box, and the fuses in the engine bay.

The light never changed one bit.

I also hooked up my volt meter to test the amps that it was drawing. I'm drawing about 2.6 amps from somewhere? Again, I pulled every fuse that I know ( glove box and fuse block) and the light never changed.


Now what?

Did you remove the cable from your alternator?

im pretty sure if you test the battery's volts while its hooked up and the cars off, and then unhook it and test it again you will see a difference if there is a draw on it when its off. i'd start with the amp, check that its not on all the time.

Originally Posted by KeithGTP03

Did you remove the cable from your alternator?

I'll go try removing the cable from the alternator.

Originally Posted by thegipper

I also hooked up my volt meter to test the amps that it was drawing. I'm drawing about 2.6 amps from somewhere? Again, I pulled every fuse that I know ( glove box and fuse block) and the light never changed.


Now what?

2.6A?! Holy Fuc! Remove the cable going to the alternator and check it again to make sure there isnt a diode backdraw coming from the alt.

So I disconnected the Alt wire and it didnt change anything. There's a constant 2.67amps roughly drawing somewhere?

Yeah I'm pretty sure I have my volt meter hooked up correctly. I put the postive probe on the negative post and the negative probe on the negative wire going to the vehicle. I have the volt meter's settings on Amps.

Thoughts

Yeah...2.6A is a short. Typical draw should be around .020 Amps. I would check your big 3 lines for a stripped jacket somewhere. And you've already ruled out any component in the car causing it.

When I complete the circuit you here the door unlock and the headlights flash. So I'm pretty sure im doing it right.

what on earth could be drawing that many amps?

Yeah I guess the only thing I haven't unhooked is the relay harnesses for my HID's.

And I guess I could unhook my big 3 and see if that fixes it.

I'm totally lost...

I forgot about the HID's. But to test current with a multimeter, connect your battery's negative back up. Disconnect the power and set your DMM to 10A since your seeing 2.6A, and place the probes to the battery wire and the battery's terminal. And wait a few minutes cause you're prolly gonna trigger your interior lights. Wait till they go out and see what it reads.

I'll go try that.

You know what.....thats probably why im drawing the 2.6 amps. The interior lights are coming on when I'm completeing the circuit. I need to wait to they go off then check.

BRB

So its drawing about .04 amps w/o my amp power wire hooked up and about .1 amps when i hook it back up.

THoughts?

My interior lights is why it was drawing 2.6 amps earlier.

but still, .04 w/o amp hooked up .1 with, either way wtf !

I would disconnect that capacitor and see what you read. But 40 miliamps is still too high. With the amp wire disconnected, I would go through your fuses again now that you have an actual reading.

Originally Posted by KeithGTP03

I would disconnect that capacitor and see what you read. But 4 miliamps is still too high. With the amp wire disconnected, I would go through your fuses again now that you have an actual reading.

I went through all of them with the test light though. Are you saying that I should pull each fuse and check the meter.

is the light not accurate to see the amp draw go away?

It's hard to see a the difference between a few miliamps with a test light. And also, Im assuming the door was open when you checked the glove box fuses, so your interior lights were drawing current. And Im not sure what year your car is.....does it have a light under the hood?

It doesn't have a light underhood. When I was using the test light the door was open but no lights or anything were on because the negative battery terminal was disconnected. I used the light just like the way you told me. If i hood up the test light to the battery it was really bright, but when I hooked it up the way I was supposed to it was like 1/3 as bright. It never got dimmer though after pulling all of the fuses.

Maybe it is my capacitor. Can they go bad and draw current when they are not suppose to ? it does have a digital readout.

Yes, if the capacitor is discharging on its own it will constantly try and charge. How far away from the battery is the fuse for the amp power line? If you disconnect the cap and the draw is still there, I would check for an exposure of wire between the fuse and the battery. If it was an exposure after the fuse it would blow the fuse. But even with the amp line out of the equation, you're still drawing about 20 miliamps too much. At this point, I would check your power and ground lines that go to the battery for corrosion...this would definitely cause some draw.