Steady electric current draw

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Kwenda
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Posts: 2
Joined: 30 Aug 2017, 15:22
Car model: Mini One 2004
Location: Poole

Steady electric current draw

Post by Kwenda » 30 Aug 2017, 16:32

Hi, I wonder if anyone has some explanations for what appears to be a problem.

Leave the Mini One, registered March 2004, 1598 cc, at the airport, and when I come back after two weeks the battery is very low. Voltage at 4 volts. All measurements taken with an expensive Fluke professional meter.
Battery recharged and tests good, no problems there.
BUT when reconnecting the battery, find a significant spark showing a current draw.
The meter shows a steady current of 0.975 amps.
All this with the car stationary, no radio, no lights etc.
No wonder the battery is flat after leaving the car for two weeks..!!
Why is there this current draw, and does anyone have some ideas on where I should look.
Thanks for any assistance..

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M60NJP
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Re: Steady electric current draw

Post by M60NJP » 30 Aug 2017, 16:38

One of the most common faults is with the final stage resistor on the cabin fan - when this fails, current continues to be drawn unrtil the battery is flat. It's colloquially know as a hedghog (you'll see why) and are about £40 to buy. Unusually most folk recommend buying the BMW/Mini part as the cheapos on Ebay are prone to fail not long after purchasing.

They're not difficult to replace, but access ain't great!!

Before blowing £40 though you could recharge the battery and then (30 mins after turning everything off) put a meter across the battery and pull one fuse at a time and see if the voltage increases.

Alan Gunn
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Re: Steady electric current draw

Post by Alan Gunn » 31 Aug 2017, 06:06

+1 on the above.
I used to like hedgehogs when i was a kid.

Kwenda
BMW Enthusiast
Posts: 2
Joined: 30 Aug 2017, 15:22
Car model: Mini One 2004
Location: Poole

Re: Steady electric current draw

Post by Kwenda » 31 Aug 2017, 06:21

Thanks to both of you I will give that a try in the next couple of days.
Will come back here with hopefully good news afterwards.

Thanks again

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