Z4 Forum - The Fountain of all Knowledge

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Grizzly9

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This one is open to all within the Z4 community fountain of knowledge.
Battery keeps draining. It's chucking out 14.2v when engine is running so I assume the Alternator is doing it's job. I then checked between disconnected Negative terminal and the Negative lead and it seems to have a 'draw' of around 1.7amps. This figure isn't a lot of difference whether the boot light is connected or disconnected.
I can run the car every day, but leave it for more than a day or two and it won't start. So I'm assuming that on one of the circuits there is a short/bad earth and is drawing a current from the Battery.
Is it a case of pulling the fuses out one by one to see 0.00 registered on the Multi-meter Amp setting? Will I see 0.00 or is there another circuit like the alarm going to be drawing some juice?
The Battery is a one year old Yuasa..? yeah I thought the same but it has a five year guarantee.
Any help or witty comments too, much appreciated. :)
 
Mine is the same, it also has a ten year old tracker which are prone to high current draw as the integral battery dies & its charger works overtime trying to keep it going-I will be attempting to remove it soon which may be a bit arduous as the info from the tracker guys was vague to say the least :roll:
Rob
 
I had this (on a Golf) and it turned out to be the alarm sounder; a new one for a few quid and all fixed. The battery was going flat in a few days.

Fuse pulling is a reliable way to do the diagnostics, you'll also need a decent clamp meter. The car needs to be completely asleep before you start and ideally you want to know the sleeping current draw range for your car. I can't help with teh Z4 but for comparison the Golf was 40-80 mA.
 
Thanks Graham, you've confirmed what I thought all along. If I called out an Auto electrician I don't think any diagnostic machine is going to locate the fault. I think all they would do is resort to fuse pulling to identify the circuit involved.
 
Anyway you can park the car up without locking the doors. There could be a drain on the locking system/immobilisor.
 
I don't very often lock the doors so I can rule that one out Mike. The only thing I can think is suspect is one of the parking sensors that gives off a constant Beep when selecting reverse. Other than that it's pulling out all fuses tomorrow when the weather's a bit better.
 
I spent months fighting a similar issue. Ended up being nothing more than a faulty battery (which was also only a year old). Worth trying a different battery in there if you know someone local with a Zed you could swap batteries for a couple of days with.
 
For the sake of knowing, I'd be taking the battery back and cashing in on my 5 year warranty claiming it to be faulty. At least that way, if the car is still playing up after that, you'll know it's not the battery :-)

I'd stick £5 on the battery being the cause though, as your symptoms sound identical to mine :D
 
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