SLOW BATTERY DRAIN
 

Hi Guys & Girls, Looking for some info on possible battery failure? The problem started about 6 months ago when it had been sitting for 5 weeks and was dead, jumped it and it was fine for 5 weeks of daily driving, then went away for 5 weeks, after 3 weeks car was started and battery dead? Now every day at home started no problem, been away for 6 days and battery dead again? Look like every day driving is okay but leave it for a few days or more and it's dead. I will get a new battery but I suppose that's no good if I have an underlying problem, any advise what/where/ how to check? :dunno:
Cheers

Get a new battery and follow the instructions in your cars manual. There is nothing wrong with your X5.
¨If you plan to park the vehicle longer than 4 weeks, have the battery disconnected from the vehicle's electrical system by disconnecting the cable from the negative terminal. Then have the battery charged with an appropriate battery charger.¨

I've had this issue on my X5, parked every second month, charging and changing several flat batteries. A simple battery switch on the negative wire was my solution.

Thanks for the info, however I can't help but think I'm not going to all that hassle for something that should really not require a disconnect? The car should sit for 4 weeks without problem surely?
Cheers

BMW is obviously aware of some kind of battery drain, hence the 4 week limit. I haven't had any problem with a fully charged battery leaving the car for a month, but only using the car every second month problems comes back rather quickly.
I also think when charging a flat battery you will not get it back to 100% and if done several times your car will not sit for 4 weeks.

I have been working offshore for 9 years overseas and never had that problem before with leaving the car sitting, this is BMW #4 and all the otheres were fine? I appreciated theat the X5 has lots of electrics but even so, I will charge it up and see if I can find the problem by using posts from this site before buying a new battery. I agree that It's probably on the way out now anyway having had 3 previous drains

cheers and Merry xmas

I would check the final stage resistor. Turn off the car, pull the key out and stick your head in the driver's footwell. If you can hear a fan going, your FSR is almost certainly bad and draining power.

http://www.xoutpost.com/bmw-sav-foru...y-problem.html

Check out my thread

Gents, Thanks for the good info, I'm in Russia right now but will check it all when I get home. The reason I am a member of the website is all the great help you get from fellow X5ers and the vast knowledge that is on here

All have a great xmas and a very prosperous 2010
Cheers

Hi there,
Theoretically your fully charged battery should last sitting with the draw of 0.02 Amps for a 180 something days. 90Ah / 0.02 Amps =4500 hours / 24 =187.5 days
That's the way it should be assuming your battery is good without any busted cell etc.
Am I right?

Diyanich,

That would sound about right and a bit more like it? Still investigating

Cheers