left turn signal blinking fast but no bad bulbs
 

Okay here is a weird one. A couple weeks ago I plugged my dads trailer into the x5 and towed it around for a bit. At some point shortly after I noticed that my left turn signal was blinking fast. I assumed a bulb was bad but after getting out and checking they are all good. I checked any fuses that seem like they could be related thinking maybe one blew and is causing this. It seems like it can't be the relay as it is only on the left turn. Kinda perplexed and this is getting super annoying. Also this may be related - at the same time I noticed this I also noticed that the passenger mirror will no longer dip in reverse regardless of where the mirror switch is.

Does it blink at a normal rate when the trailer is unplugged?

If the trailer is disconnected suspect a bad turn signal socket. If it is only doing it when the trailer is connected, possibly a bad ground to the trailer.

I haven't had a trailer plugged in since I noticed it. I noticed it shortly after I had dropped the trailer but it may have started while it was still plugged in.

I'm experiencing the same issue on my right turn signal. I replaced the rear bulb holders a few months ago, the fronts are brand new aftermarket units, and all bulbs are new. I am thinking it may be a failing relay. Anyone know where the indicator relays are located?

Behind the headlights, as in a tight fit for hands unless one is a surgeon...

I had the fast blink, changed bulbs, cleaned socket, etc.

My Indie changed the relay: he let me watch, and it's not difficult but takes some dexterity and small hands. He's done hundreds on all kinds of BMW and said it is quite common.

Took him 5 mins; would have taken me 30 and scuffed my hands and knuckles.
GL, mD