e36 touring, something is draining my battery!

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Avtovaz
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Mon Jun 07, 2010 8:30 pm

I have just bought a e36 touring as a cat c write off. I have found that the battery goes flat over night.

I noticed today that when the car is stood, i can hear a little motor or something in the dash. The car has climate control and im wondering if its somthing to do with that?

Please help as i need this car on the road asap!

thanks!
johnna
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Mon Jun 07, 2010 10:19 pm

I had a problem like this on a Pug (I know...) it turned out to be a faulty diode on the back of the alternator, dripping the stored charge down overnight.

A replacement alternator and I was giggling!
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Raj_p
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Mon Jun 07, 2010 10:27 pm

How old is the batt? disconnect the battery over night and see if it still drains, could be a duff batt. failing that, try with the car off, put a volt meter across the battery, and pull a fuse at a time, and see if it makes a differnce, then cross ref the fuse with the booklet to see what it powers, then you will know what the issue is.
Avtovaz
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Mon Jun 07, 2010 10:42 pm

I have asked on a few other forums and i have got it down to, inthe climate control on the dash there is a fan, and its that spinning that is making the battery flat. I just dont know why its spinning!

thanks ;)))
xavi1980
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Mon Jun 07, 2010 11:50 pm

You will find that behind the dash of e36 with climate they will make a noise with the key out but that's normal, it's the resistors and it's normal but that's not where your drain is. Your drain no doubt is a bare wire somewhere touching the chassis
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30316
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Tue Jun 08, 2010 3:38 pm

It is a common problem on E36. If you hear the whiring sound then it is the fan that is turning. It should normally close once the ignition is turned off. The problem is the resistor pack commonly known as the "hedgehog".

One way you may be able to stop it is before switching off the ignition turn down heater/climate control fully off. This may stop the whiring that you are hearing. Well it did on mine and the battery no longer goes flat. Though mine used to go flat if the car was not used for a week or.
oomz1975
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Tue Jun 08, 2010 10:56 pm

Check the fat negative cable coming off the battery, when I had some work done on my e36, I was having the same problem. It turned out that the negative cable wasn't properly earthed.
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Avtovaz
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Sat Jun 12, 2010 7:55 pm

I put another battery onthe car today, and the little fan is still spinning when its all locked up.

So does that mean i need a resistor or a hedghog?
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