Pause in startup electric process - auto headlights
 

I'm puzzled by this one.
When I start my '03 X5 3.0i, the auto headlights function as expected for exactly 12.33seconds. Then they shut off for exactly 60seconds. Then they function as expected permanently until car is turned off. I have replacesd the RLS sensor (just the sensor and not the prism) but the behavior didn't change.
I am now thinking that something is happening with the startup of the electrical system and it is manifesting a symptom in the auto-headlights.
If I change the headlight setting anytime during the process (the first 1min and 12sec) nothing is different (meaning that if I turn the headlight switch to auto at 10 seconds after starting the car, then the auto-headlights will shut off 2.33 seconds later and turn on again exactly 1 minute after that.
I have measured these times with a stop watch because they are exact and consistent.
I swapped the fuse (#41) and that also didn't change the behavior.
Any ideas on what to troubleshoot??

My battery started to die the other day. When I went to start the car the 'last' time, the xenons came on and flashed a couple of times while the starter clicked... This was strange as I had the headlights to off.

Might want to monitor your battery voltage using the hidden cluster menu and see if your battery is winding down.

BMWs get very strange when the battery starts to go

My battery started to die the other day. When I went to start the car the 'last' time, the xenons came on and flashed a couple of times while the starter clicked... This was strange as I had the headlights to off.

Might want to monitor your battery voltage using the hidden cluster menu and see if your battery is winding down.

BMWs get very strange when the battery starts to go

Dan, did you do any programming recently? was there any water damage in the passenger foot area? what happened when the problem appeared for the first time? cold you correlate it to something external? like jgold said - the battery gives out some "death fluids" before going kaput... how old is your battery, and what shape is it in?

Thank you for the battery check advice. I checked my battery (BMW / Exide May 2009). It had a voltage of 11.7 when the vehicle was off, and 13.2 when on. So I replaced it (Walmart Everstart Maxx h7). Then I was all excited for it to resolve the issue, but nothing changed.

I have now returned to thinking the problem is with the sensor. This weekend I'll probably use fishing line to remove the prism and remount it.

If that doesn't fix it then my wife will just have to use the standard on/off switch for lights....rough life :)