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Old 01-21-2013, 11:32 AM
dollarshopper dollarshopper is offline
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Location: Finland
 
Join Date: Jan 2013
Posts: 5
Mein Auto: BMW 730Ld F02 2011
BMW F02 2011 powers on itself after 1h ?

All,

this is my first post, just joined the forum. Rather than asking the local BMW dealership, we would likely get much more information from here, and have it shared at the same time. I have a 730Ld (F02) 2011 model; bought from BMW dealer in Germany few months ago; built September 2010.

For the reasons that belong to another issue and thread, a few weeks ago I installed a datalogger in the car to monitor and record the battery voltage and ambient temperature changes. I need to mention also that the voltage measurement is taken from the 12V (cigarette lighter) output in the dash - i.e. the power is there when the car is "powered on".

As of yesterday when glancing through the measurements from last week, I came across something *unexpected*, and would like to do a quick poll with you if anyone could check whether your car exhibits the same behavior. Even better, if someone could explain why.

So, every time I leave the car (i.e., stop the engine, turn ignition off and lock the doors), the power (in the 12V output) remains on for another three minutes before it drops to zero. What is interesting, and unknown to (at least) myself, is the fact that the car powers on itself exactly 1h (60 minutes) later for another three minutes. Why is that? Anyone knows?

When I saw the first instance of this in the datalogger output, I thought it might have happened because of some radio interference causing the car to power on. Looking more carefully the output of the datalogger, I came to realize that this happens *every* time I stop the car, and it is exactly 60 minutes from stopping the engine (or 57 minutes from the time the power in the output went down).

As I now have evidence from whole week of this happening every time, and in exactly the same pattern, it is no longer a coincidence or radio interference; it is BMW programmed behavior - whether intentional or not.

Initially my main concern was whether the doors get unlocked at the same time for those three minutes, and someone happening to be nearby could enter the car. To see whether that happens, I decided to watch it happening. So when I came back from work today and knew the power on would happen in 1h, I set an alarm to go off 58 minutes after I turned the engine off. The 58 minutes goes by, my alarm went off, and I went outside (without my car keys), standing next to the drivers' door to see what exactly happens when the power comes on.

At exactly 1h timestamp, the lights in the gear lever, start/stop button, and few more dash lights came on; but to my relief, no doors unlocked, no fans or anything else started that I could observe, just those dash lights which remain on for 3 minutes after powering off the car.

So, no major worries, but I remain curious as to why? Why exactly 60 minutes after turning the ignition off?

I wonder if it is related to the optional equipment fitted, or if it is a standard behavior on all F01/F02 2011 models (or older/newer ones). Could some of you check whether the same happens with your vehicle and post it here? Even better, if someone knows why is this happening? (I'm afraid that asking the local BMW dealer would be waste of time...)

I will try to attach one example datalogger sample on what's happening - not sure if I succeed as it is my first time in this forum to post (and with a picture...)


Thanks a lot for any comments/replies.
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