luvmyride

I have had my 08 535i for two months. Since I got it, the AEs dimmed on or off when the doors were locked/ unlocked. Also when I turned the car off the stereo would say on until I locked the doors or pushed the ignition button a second time (have comfort access).
Starting today, I don't get AEs on with locking and the stereo goes off as soon as the engine. I also don't have the headlights stay on after leaving the vehicle. The stereo also is on mute every time I restart the car. Could this be caused by a low battery? I have had one instance 3 weeks ago when the car was completely dead for no apparent reason. I took it to the dealer and he said the battery tested fine. He said If I have more trouble, schedule an appt (about two week wait to get in)

luigi524td

YUP ... failing battery could be at the root of it. And it's very difficult / impossible to do a "conventional" full load test on the battery while installed in the car. So, your battery may report 12.x volts and still be failing. There are lots and lots of posts about "driving profile" ... and your dealer may tell you you don't drive enough mile a day to keep the battery charged. Our cars are power-hogs!! The IBS is sometimes part of the problem - best to get these sorted out under warranty because the whole R&R will run you about $600-$700 ... incl battery registration.

That's one HUGE reason I'm so skeptical about BMW's recent news about expanding hybrid choices to the 5'ers. If they can't get a proper battery-charging set up right after 7 years of e60's .. what is my level of confidence they'll produce a hybrid that doesn't require drivers to travel with an extension cord connected to the grid!!!

luvmyride

Thanks for the reply, I thought that was the case. Today I get in the car and the clock had lost over 10 min. overnight. I changed my brake pads all the way around which took a couple of hours (lots of time chatting). I locked it and put the key up. When I got done the car BARELY cranked over and all my presets are gone. What a PITA!!!
I called the dealer this morning and they never returned my call (they are closed now)
I'm afraid to drive it.....

Gilgorm

Your battery is on its way south. You may be helping the demise of your battery. With Comfort Access you have to push the start button a second time all the time(at least in my car) otherwise the radio and lights will stay on. Also if you have the headlight switch to auto (far left) then some interior and exterior lights will come on and again drain the battery every time you open the door which is annoying in broad daylight.
Just for battery preservation, I turn the lights on auto AFTER I start the car and always push the ignition twice (otherwise, my radio will go off after about an hour).
Complain to the dealer about the poor battery and, if under warranty, get a new one.