Flat Battery (I think) but not sure how...

[imolazed]

Hi Guys

Over the past week I've been working on my MC on and off (machine polishing). Last night I started it to move it out of the garage and turn it round, all went fine, back into garage and switched it off. Finished up today and went out to take it for a drive, turned the key and got lots of warning lights and bursts of starter, also the windows don't drop and go up and down very slowly. So...I'm thinking flat battery, not the end of the world.

BUT..what's confusing me is what ran it down? I didn't have the radio on or lights or anything like that, in fact I doubt the key was even in the ignition. I will have been opening/closing the doors and boot which I guess would be using very slight bursts to drop windows and push the boot popper but surely this couldn't flatten a battery?

Also does anyone know what brand the battery should be? It's an 06 UK Z4MC. Just wondering if it has maybe been replaced before with an inferior or incorrect battery.

Thanks in advance.
John

 

[cj10jeeper]

You probably just drained the battery and starting it last night was it's last store of power. Even without the key in every time you open a door, etc. you activate the systems for 15 mins until it hibernates and use a bit more.

Stick it on a charger overnight and it will probably be fine. If not then check you handbook for the recommended AH of the battery

 

[TO//M]

You will need a 70AH battery. The OEM replacement from BMW goes for $400! I'd definitely try charging it but four years is getting the the end of its expected service life.

 

[imolazed]

Ah I see, I didn't know everything kicked in for 15mins...that would probably explain it. With that in mind the systems were probably on for hours over the week!

Thanks cj10jeeper.

On the plus side however...it now looks like this...

 

[cj10jeeper]

It's certainly looking good

The 15 minutes hibertante time is an odd one. If you open a door turn onthe ignition or anything then the central systems kick in. You can see it when various lights come on from opening a door than from teings like the sat Nav that needs to be left off for 15 minutes befor it reboots to the splash screen.

Could need a new battey but then again my original X5 battery was fitted into a Jeep 2 weeks ago after 7 years of use and 1 year int heh garage and then pulled a 2 ton Jeep up many an incline over a weekend of competition

 

[imolazed]

Jump started the car earlier and all seems fine (though the traction control light stayed on...).

I've just dug out my old trickle charger, can I charge the battery from the jump start points or do I need to attach it directly to the battery in the boot?

Thanks

 

[Darkman]

Connecting to the jump start points is fine, but check all the in car switches, had mine go flat and had to get the aircon, fan and heated rear screen reactivated at the dealer.