bauska

Here is the problem I am trying to resolve. I have 2008 550i, automatic, no comfort access. Sometimes when START/STOP button is pushed - nothing happens. All lights in dashboard go on, no error messages and nothing happens.
Luckily for me it is a CPO and several trips to dealer has not solved the problem.

Dealer so far has changed the following parts:

Crankshaft Speed Sensor (part# 13-62-7-548-995)
Gear Selector Switch (part# 61-31-9-204-091) - twice - the second time as a precaution
Starter (could not find the dealer receipt)
Brake light switch (part# 61-31-6-697-601)
Battery negative cable (part#12-42-7-603-567)
Adapter for IBS (part# 12-51-7-615-476)
Right now dealer says that battery was dead this morning.

And still my car sometimes does not start. When it does not start, if you leave it to sit for 15-20 minutes, it starts up, like nothing happened.
Has anyone ever experienced something similar? I am trying to find the part that might be at fault, but does not register any error messages.

is a video of the problem.

Thanks,
Egils

Gee_115

If you haven't resolved this go over to bimmerfest post there with a special request to a member called BMW_tech. This guy knows his stuff and is an actual bmw tech. Search his post and you will see what I am talking about. If he can't help you then I don't think anyone else on these board can.

EUAutoHaus

Hello Egils, I have watched your video. I worked at dealer for about 8 years before moving on. We can rule out the starter since it's been replaced. The IBS may be flaky but that would require more tests. It sort of looks like your immobilizer is not in sync or not responding properly. Has the dealer done any software updates or hooked this car up to their equipment? I would assume they have because some of those parts mentioned above do require adaptions to be reset. If your battery was completely dead your car would not respond this way and should still attempt to crank. This is exactly what happens when I reprogram or update a car and do not re-align CAS. Once CAS is re-aligned the problem is solved. In your case the problem you stated is intermittent so I am thinking it to be software related. Take your car back to the dealer and ask them to look at software.
Good luck,
Sammy

bauska

Thanks Sammy, I will let my dealer to know your suggestions. I will get back and report how it went.

Thanks again,
Egils

tbanks

i have been having same Problem and dealer has yet to resolve! Did you get it resolved?
thanks

bauska

I am glad to help! It ended up being the following problem:

Control Unit (Intergrated Supply), Part# 12-52-7-510-638

It is a unit that contains fuses and it is located on the passenger side beneath the micro filter.
I had this problem then and now without any explanation. It ended up that I could not start in my garage and my local dealer came out to my house to fix it. It was a manager and he stated that this was a problem for 7-series in the past and that he does not seen this in 5-series.

Let me know if this helps!

Egils

tbanks

thanks

i will look into that

i saw that unit with the other modules when i was checking for loose connections

thanks again

tbanks

i replaced the Intergrated Supply Module today
thanks again