AP Sales

I had to replace passenger front door handle for same problem. It was the only problem I had with the car. I think cost was about $500.

Rudy

The dealer may or may not be on to something...

Clearly, some owners have solved this problem by replacing the door handle but others have not. Also, leaving the key near the car should not be an issue even though many people are told this (or believe this to be true).

If my dealer wanted to charge me for this repair, I'd probably ask them to agree to credit me back if the problem wasn't solved. The battery drain issue can be a tricky one to diagnose and some dealers get it right and some do not. I don't think the customer should have to pay for a less than competent dealer's attempts to troubleshoot things or fix something that isn't broken...

Good luck with whatever you end up doing!

luigi524td

Rudy, I trust your knowledge about these things ... BUT in a recent tire service at an indy shop they left my CA FOB in the car for the several hours and my battery discharged sufficiently that I had to have a jump start. Perhaps having the FOB in the car (rather than merely "in range") causes more parisitic systems to remain on-alert and cause a battery drain?

Rudy

I hear you but...in a car that's operating properly, you can leave a CA fob in it for days and there won't be a problem. My earlier point was simply to illustrate that the car is supposed to go to sleep properly.

Is it possible that the Indy shop kept opening a door or trunk throughout the time they had the car? This will constantly wake the car and will, after a few times, cause the battery to drain excessively...

romansg

Have an 07 550i that had similar issues; after a few trips to the dealer, they discovered a faulty drivers side rear door handle unit was causing the problem. I too, recommend keeping the FOB away from the car at night, and ensuring that you leave the FOB in the ignition when washing your car (to avoid unneeded cycling of the door access mechanism). I haven't had any issues for a year and a half since the originating problem was resolved, but had two different TCU's installed, a new battery, software update, all done on warrantee. So far so good; good luck to you.

luigi524td

Open Trunk!! That was the likely culprit ... I guess the systems don't shut down after some predetermined time (say 20 minutes) if it's detected that the car is idle. Our darn cars must be too smart for their own good

Gilgorm

As I noted in prior posts, my 535i had this problem last July. The Comfort Access main module controlling all the door handles was first replaced, then my electronic gear shift (LCI only)was replaced since it was staying up late to chat with my battery and finally in week three the after-market Boomerang anti-theft system was removed because it thought the car was missing and was trying to 'phone home' and was also draining the battery.
When my car was in the January crash and spent two weeks in the auto body shop it was dead when I went to pick it up. Two doors, hood and trunk were open for long stretches (so long that the lights went to sleep on their own). Boosted to drive home.
No problems since, even in COLD weather with no garage.

Rudy

They do shut down after a pre-determined time but quite often, the timer is activated again and again until the battery dies. In other words, if your car is parked and sleeping and you open the trunk to get something out of it, you just woke the car up. Regardless of whether or not you close the trunk, the sleep timer is now ticking down the time it'll take to put the car back to sleep. While the car is awake, there is an increased battery drain.

What often happens is that as a car is parked, people will open and close the trunk or doors repeatedly and they think, since they only opened it for a second and closed it again, that they are not causing any battery drain. In reality, they are, in fact, causing the battery to drain itself. Many people assume the CA key fob is causing the problem when it's really just the constant opening and closing of things that's causing the drain...