How to locate an energy drain?

[Andrew_Pakula]

Does anyone know how do I go about locating an engery drain?<P>Something is draining power from my battery but it isn't anything obvious like a light or anything like that.

[mx32b]

It's been awhile since I took Physics and my mind is mush right now (summer time!), but anyway, how can you be sure you have something draining to begin with? Like I said in another thread, the battery just died in my moms van, could be the same thing. <P>So my question/advice would be to hook up an ammeter and see if theres a current flowing when the cars off. Now I call this a question/advice because I can't remember from the work on circuits we did in physics class how circuits work, and I'm not sure if hooking up an ammeter would tell you anything. Perhaps someone could fill us both in and build on the idea?

[Andrew_Pakula]

Well something is draining the battery.<P>Nothing is ever left on that is visible, everything always appears to be all off.<P>The battery is fine and has been tested twice now and it is fine. There for something is killing the battery over night if I leave it.<P>Tonight I unhooked the battery connectors so that it doesn't drain the battery again. However I will have to find what is wrong somehow soon.

[Sonicxtacy02]

what i would do to confirm its not just a faulty battery cell is check the readings before removing the cables, then check them again in the morning. I've had batteries that held a solid high current charge but when the battery just sat it died [img]shrug.gif"%20border="0[/img] <P>Good luck

[Andrew_Pakula]

Well it was put on the tester last night and it appeared to be working and fine because it was charging it and was not coming back as a bad battery.<P>However to be safe last night I unhooked the battery clamps.<P>I then drove to work today and left the car for about 3 hours and then tried starting it up. It was dead again, there was still power there but not enough to start the car up.

[Maddbuck]

How old is your battery?<P>If it is more than five years I would just replace it to be sure. That way you can illiminate the battery as the problem and move on to find the cause of the drain.

[Andrew_Pakula]

The battery is only a year old.

[92RedMX3]

Ok check this out, a modern marvel of electronics. Go buy the cheapest 12v light, I mean a dome replacement, whatever is the cheapest. Now take those two wires and this part is up to you but you can breakthe top off a fuse and rig it so that one wire has each part of the fuse connection or what I would do is take a crimp connecter that looks like a U shape and crimp one to each wire then cut off one of the U shapes metal pieces and tape them together so that the metal doesn't touch and you will once agian have a series circuit, not a short circuit.<P>Ok, now that you have your connecter rigged take it and pull a fuse with the car off totally and see if the light lights up, If you do then that circuit is active, meaning a possible drain. <P>How does this work? Well it creates a series circuit, one side is the positive and if the other side pulls a load it acts like a ground since it does have a ground and it makes the light come on. It will probably shine bright when you find it. I think that covers it. The whole connecter rigging is to make it very easy to pop out the fuse and touch your tester to it so that you can move on if there are a lot to go through. It will just save time in the end. Plus going though a lot and having to hold something a special way get tiring REALLY quick.<P>Any Questions?

[Andrew_Pakula]

Well it turned out two be two problems.<P>First of all there was a short somewhere which was causing the the battery to drain fairly fast if you left the car off.<P>Also the alternator wasn't outputting enough power, it was outputting a bit but not what it should be doing so I got the alternator rebuilt.<P>Anyways everything is fixed up now and the car is running good again

[Sonicxtacy02]

how much for the alternator rebuild andrew?

[Andrew_Pakula]

Like $150(cdn), plus labour to take it out and install it back in.