I take it no one has invested $150 in the purchase of an Optima battery?

Optima 12 Volt Performance Battery - Sealed Batteries by Optima

I doubt the X5 is anyone's first vehicle. We all know BMW is going to drag their feet on this issue.

Lots of vehicles have suffered from such issues. I remember my 1997 Jeep Wranger has a similar issue and went through multiple batteries (I owned two 1997 Wranglers a 4-cyl and a 6-cyl.).

If this happens to me, I'll just replace it with a "Yellow Top." It exceeds BMW's specs., hence there would be no warranty issue.

I agree with all: an X5 that discharges its battery after sitting for several days is suffering from an error.

It's entirely possible that BMW purchased a massive batch of bad batteries. Batteries are all rated, and there are tremendous variables between batteries. In fact, when it comes to high performance batteries, they're rated in terms of the time they take to discharge when a certain load is placed upon them.

There can be variances of 20% to 30%.

Battery tender requirements are fine, but having to do so, in a tepid climate is ridiculous.

Is anyone in California (Southern California), or Arizona having this issue?

I'm going away Thursday-Monday and my X5 35d will not be started. We'll see what happens.

BMW will certainly be getting an earful if my 35d doesn't start, and this thread is excellent evidence for all of us, so keep it going.

I drive it to and from the coffee shop M-F, which is less than one mile away. It sits on my driveway outside at whatever temperature the Chicago suburbs happens to be. (recently it's gotten below Zero overnight).

No battery problems and no charging needed. Recently I was out of town for 17 days and the Explorer sat unused. Started like a charm upon my return (as did the 2005 Ford Focus with the OEM battery).

As the 17 day trip was in the X5, I cannot speak to it regarding sitting unstarted for days in the cold. But, as an aside regarding the other topic of simple cold weather starting, it took right off at 5 degrees F one morning after sitting all night in the hotel parking lot.

)Seriously now, you think it is normal for a vehicle sitting unused in 10 degree temperatures to not start after five days of inactivity?

If that were the case, there would be thousands of cars not starting at the O'Hare airport parking each week in the Winter, and just imagine the Minneapolis airport parking lot.

If you really want, I can do the calculation of the specified maximum milliamp load for a locked X5 (40 milliamps after 60-70 minutes with TCU, 30 minutes without TCU) vs. the 90 Amp-Hour rating of the battery, adjusted for a temperature of 10 degrees and the normal self-discharge of an AGM battery over five days (1-3% per month).

:iagree:...I parked in outside lots at EWR/LGA/JFK for 25+ years, with cheapazz "company cars", '74 to 2001. Sometimes for 2+ weeks at a time.

Admittedly none of those metro NY airports are in the Tundra, but I never needed a jump, for any of my crappy company cars, over all that time.

Back at the BatteryBoosterRanch, I suspect some owners have more starting/charge holding problems than others; it may be anecdotal, it may be luck,
but the "system" in these cars is just so-so, for many, imo.
And, I use a BattTender on my X, and it's a slight PIA, but necessary...

:iagree: There's a problem with the car in a case like that.


Regarding Optima batteries: There are reports of leakage and failure with those batteries and they cost close to $200.

OEM batteries are usually more than sufficient for any make/model car.

+1

So. Is the really cute waitress off on the weekends? :nanana:

Funf Dreisig

Well, not exactly...

The Significant Other goes with me for coffee on the weekends, so we take the "good vehicle" (her term), the 2005 Ford Focus she uses as a daily driver.

The X5 was a replacement for the 1992 Explorer with 198,000 miles on it; however, since it still runs and the insurance is only $150 for six months, I decided to keep it around as a "coffee shop vehicle" until Winter is over, rather than run the X5 in salt slush. Unfortunately, the tires are almost bald, and the 4WD no longer works, so it makes for fun times if it's snowing.

But to be more direct in response to your question, the cute one is still there on the weekends; however, I pretend not to notice...

+2... I am in Toronto and just returned from a trip to Europe. My 35d was left in the garage for 37 days and started immediately (without any warning lights) when I returned. I have to say I was a bit worried about potential dead battery before my trip - after reading the various posts in this and other forums on this subject. The only thing I did before I left was to make sure I locked the doors properly (I read somewhere that the car continues to carry various electrical diagnosis if doors are not locked) and touch wood - started without any issue after 37 days.

My 2 cents !

That would be my story. And would stick to it bro' :D

Funf Dreisig