did that, they had my 5 series for a week and found out that the idrive display was 'waking up' the car and combined with the short trips killed the battery.

I agree with your comments but we are just now starting the whole process again with the 5er and now the X5 electrics have started to die (sure sign of battery down). Here we have paid over $320k for the two cars and I look like having to buy a battery charger to keep them going....

kinda pathetic......

Wife is away with family interstate so I am taking the X out for a day of running around town as that seems to be what it needs, then when the family gets back we'll do the same with the 5er.

I have learned with BMW though to go find my own solution as the dealer can only do/know so much....

This might give an early warning of the battery getting too discharged and save people some aggravation:

http://www.argusanalyzers.com/filead...g_brochure.pdf

With the battery where it is on the X5, installation might be an issue, but since it says it has an audible alarm, you shouldn't have to actually mount the gauge on the dash.

Hard to spit into the wind...with the plethora of low/dead batteries here,
and with all the gizmos/potential drains, it just seems to me that one should
consider a less than $50 Battery Tender or its cousin, and apply it once in awhile.

Yes, the Teuton engineers should have figured this out. Yes, there should
not be such a seemingly high instance of battery drain/failure...but, a Tender
does wonders. I've been using them on my m'cycles and cars for 2 decades.
Yes, my cars in the 80s and 90s rarely, if ever, needed a Tender. Today,
they seem to...my '01 X5 and '02 Vette, not driven daily, live on them.
I got 6 yrs out of the oem X batt. and 6 years out of the oem Vette batt.

An occasional application of a "Batt Tender" is not hard work.

GL,mD

Agree. One thing I find interesting is that some older BMW's like the 7 series had 2 batteries to fully support all the systems. Interesting that BMW didn't continue down that path, though I can obviously see the disadvantages.

Well, my point is that I personally believe that they have figured it out, and that the vehicles with battery problems have a problem that should be fixed, i.e., something is not going to sleep like it should, leaving an excess drain on the battery, or the battery is bad.

If there is an excess drain on the battery due to some module not going to sleep, the battery tender would remove the symptom. But before I resorted to regular use of a battery tender, I would want the dealer to do a load test and determine (a) how long it takes the vehicle to go to sleep, and (b) what the current load is when the vehicle does go to sleep.

My issue is that I think many dealers just automatically go to the "use a battery tender" "solution," rather than doing the diagnosis work to determine if there is a real problem/defect with the vehicle.


Can anyone with access to BMW service documentation perhaps look-up what the "sleep" current drain range is for the X5? With that number, one could determine rather easily, if they had a reasonable multimeter, whether or not the vehicle had an excessive current drain.

I contacted BMWNA and waiting for someone to get back to me. There are a ton of issues like this on other forums and came across this SIB.

Yes I could hook up a charger to my battery at night, but last I remember I didn't buy a tesla or an electric car. I had a GM and they are known for faulty batteries and they never charged me a dime to swap it out let alone $665. Even then the battery didn't fail until 5 years later.

Thanks much for the SIB!

It made reference to another SIB which had this information for the maximum "asleep" current for BMW models:

E31 50 milliamps after 16 minutes
E32 50 milliamps after 16 minutes
E34 40 milliamps after 16 minutes
E36, Z3 30 milliamps after 16 minutes
E38 50 milliamps after 16 minutes
E39 40 milliamps after 16 minutes
E46 40 milliamps after 16 minutes
E60, E61, E63, E64 40 milliamps after 60-70 minutes
E65, E66 40 milliamps after 60-70 minutes
E53 40 milliamps after 16 minutes
E70 40 milliamps after 60-70 minutes with TCU (30 minutes without TCU)
E83 40 milliamps after 16 minutes
E90, E91, E92 40 milliamps after 60-70 minutes with TCU (30 minutes without TCU)
E85 40 milliamps after 16 minutes E52 50 milliamps after 16 minutes

Hopefully the dealers do the current test when they see repeated battery problems.

That's a good find. Here is the latest version of it since it has already been updated a few times:

SIB 611305
SIB 042502
SIB 041102 (in 3 parts due to upload size restrictions)

See also: (referenced in one of those SIB's)
What causes car batteries to fail?

talked to my dealer today about battery on X5 and they are going to look into installing an AGM. It's now going straight in after the 5er...

they were also quite interested in the battery monitor.....

I have asked about poss of installing a heavier output alternator (ie does one exist) and they are looking into that as well, although have suggested that as the install is quite a big job (water cooled?) I might be in for a shock $$$$.

Cheers

J

X5M, excellent links/pdfs. I especially like the Battery University link!

What causes car batteries to fail?

Bookmarked and, everyone should read it, imo. And, it supports most
of the good info posted in this thread, imo.
BR,mD