SOS - X5 dead

raf215 · #1 05-22-2010, 07:05 PM

Went out to work on replacing the radiator overflow hose and X5 has given up the ghost - no interior lights, won't even turn over. Got hosed replaced but had to work today so had a look tonight. Thought I'd just jumper the X5 with my Tundra. Got everything hooked up, tried to start but just a clicking sound. So if the battery in the X5 was completely gone, shorted cell, etc, would it keep the battery "jump" from being able to start the X5? Can pick up a new battery tomorrow but don't really want to 'shot gun' the problem . . . thanks in advance - 2002 X5 4.4i

Weasel · #2 05-22-2010, 10:41 PM

With the battery that dead it will take quite a few minutes before it has enough power from the jumper cables to crank it. If the battery is many years old it may have just died, but there is a good chance that something stayed on that killed it. Hopefully you don't have a parasitic draw to track down.

raf215 · #3 05-23-2010, 09:57 AM

Tried it again this morning waiting longer this time and the X5 started up. As far as what may have drained it, we're pretty sure it was because the interior lights got 'turned on' by the window installers when they installed the new window and we didn't notice it until that night. Pulled the spare out to have a look at the battery - it was a BMW battery but I don't know if it's the original since the only label just had BMW part #. Also noticed the 'indicator' light was black so wondering if we might be able to just get it re-charged or it's time to replace it.

Weasel · #4 05-23-2010, 04:02 PM

If you want to try a good recharge on it I'd use a high amperage charger and leave it on there for a while after it is charged as this helps knock the sulfation off the plates inside the battery which allows a better/deeper charge on the old battery.

julezw · #5 12-31-2010, 02:35 AM

Hi Weasel,

Could you elaborate on the recommended charger you mention. I am a newbie to car maintenance but all the electrical gremlins Ive been having prompted me to disconnect my battery.
I too have a near black indicator on my oem battery. The battery is now 6 years old I am wondering whether to just be rid of it or charge it. If I charge it though do I need an official BMW charger kit or just some standard spec tech from an auto store?

thanks in advance

dragoncoach · #6 12-31-2010, 02:50 AM

Most OEM batteries are usually toast after 4-5 years. Some longer some shorter. Some batteries just die with very little or no warning...especially in the cold. If you got 6 years of service, consider yourself lucky and seriously consider a replacement soon, especially if your wife drives it.

julezw · #7 12-31-2010, 03:06 AM

Thx Dragoncoach,

The other half does drive it. Will look into getting a new battery. Hopefully I'll be able to get an OEM at a reasonable price.

Weasel · #8 12-31-2010, 09:26 AM

If the battery is 6 years old it is on borrowed time... definitely replace it. But to elaborate on the charging method mentioned... When a battery is fully charged the sulfur is suspended in the fluid, as it becomes discharged the sulfur soaks into the lead plates. When a battery becomes fully discharged some of the sulfur gets "stuck" in the plates (called sulfation) which translates to a lower total charge. Most "smart" battery chargers nowadays have a desulfation stage built into them where it puts extra high voltage (like 16+ volts at 40+ amps) to force the sulfur back out of the plates into the acid.

When I sold my E36 just over 2 years ago it had a new battery, but then it sat for 2 years after my friend wrecked it. He gave it back and I was able to revive that battery by doing this a couple times. (fully charged with desulfation cycle, load tested the crap out of it till it was low, then charged with desulfation cycle again) The battery has been ok since I did that about a month ago and I only started/ran the car about one a week max since.

villajoe · #9 12-31-2010, 10:00 AM

I'd get a new battery if it's already 6 years old.

I read recently people were getting Bosch batteries at Autozone for ~ $100.

julezw · #10 12-31-2010, 05:35 PM

Weasel, nice summary on how these batteries age and are remedied. I have read lots of stuff but want to ask pointedly whether the old battery could be causing my electrical woes and if so has it damaged my gear permanantly? Bluetooth dead, sunroof wont return from fixed position? I also found this nice thread thanks to x5 meister:

http://www.xoutpost.com/bmw-sav-foru...w-one-fyi.html

So in addition to getting a new battery I'll be getting a CTEK charger and cigarette adapter. Still working out which battery to get. I did come across the Bosch batteries Villajoe, as Bosch should be readily available in OZ and seem to have a good rep. Looking to get nationally rather than internationally.

thanks guys