550i code cataclysm

[MJ535]

I posted a few months ago about a few codes that had a common voltage problem. Oddly after a couple resets it stabilized and it's been great for a few months. My car is a 2010 f07 550i GT.

Over the weekend I decided to try and troubleshoot the non-working comfort access driver's door handle. Battery was disconnected. I wasn't able to find the problem (I suspected a broken wire) and buttoned the driver's door up.

I reconnected the batter and started it and I have multi-system failure. Level control (air suspension), brakes, transmission (slow, not limp,), steering assist is off, airbag light, 4x4 system is off line, brake codes...70 codes in all. The first one I saw was"parking brake limited" before I started it.

A nightmare. I tried clearing them with Carly and it doesn't work.

Help.never seen anything like this.

[MJ535]

More info. The speedo doesn't work, tach does. Gas gauge is fluctuating when driving between 3/8 and reserve.

[MJ535]

Everything seems to go back to the speedometer. I think if I can fix the speedo, I can get back to operating. Is the left year wheel sensor the speed indicator for the speedo on this car?

[MJ535]

Everything seems to go back to the speedometer. I think if I can fix the speedo, I can get back to operating. Is the left year wheel sensor the speed indicator for the speedo on this car?

It was one 5 amp fuse tied to the door locking mechanism. Blows my mind that BMW can't better separate the systems that this single insignificant issue can take the whole car down. I knew I had a problem because like a lot of folks I have the comfort access door handles that create wiring fatigue issues over time.

Pretty unbelievable.

Hope this helps someone.