BMW Z3 - Battery keeps discharging

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Fri 20 Apr 2018 10:13
BMW Z3 - Battery keeps discharging - Steveieb
The car I left for about a week at a time but refuses to start every time until the battery is charged.

How can I check whether there is a leak some where and can you disconnect the battery if necessary?
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Fri 20 Apr 2018 11:48
BMW Z3 - Battery keeps discharging - Peter.N.

Leave the car for a few minutes with the engine and everything else off and connect an amp meter in series with the battery, remove one terminal and connect one lead to the battery and the other to the terminal. It shouldn't read more than about 50 m/a, if its much more something is drawing current. Try removing one fuse at at time until the current drops then find out what that fuse does.

Firstly you could try disconnecting the battery when you leave it and see if the same thing happens, in which case you need a new battery.

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Fri 20 Apr 2018 11:48
BMW Z3 - Battery keeps discharging - Peter.N.

Leave the car for a few minutes with the engine and everything else off and connect an amp meter in series with the battery, remove one terminal and connect one lead to the battery and the other to the terminal. It shouldn't read more than about 50 m/a, if its much more something is drawing current. Try removing one fuse at at time until the current drops then find out what that fuse does.

Firstly you could try disconnecting the battery when you leave it and see if the same thing happens, in which case you need a new battery.

Sorry about that, told me it hadn't posted.

Edited by Peter.N. on 20/04/2018 at 11:49

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Fri 20 Apr 2018 12:34
BMW Z3 - Battery keeps discharging - Steveieb
Many thanks Peter will try that .
Was a bit nervous about losing the radio code but I don't think it has one.

Cheers
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Fri 20 Apr 2018 12:58
BMW Z3 - Battery keeps discharging - elekie&a/c doctor
As the car is based on an E30,there is not much to go wrong on these.Have you had the alternator and battery tested?Any add on kit fitted?
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