One problem related to turn signal has been reported for the 2014 BMW 328. The most recently reported issues are listed below.
I received dashboard warnings that my left rear brake light and turn signal were not working. This warnings were intermittent. I changed the bulbs, but that did not fix the problem. I then looked and the connector to the light housing and saw that pin #3 had melted/corroded. I did some research and found that this is a common problem for this car, and that on a previous model year, there was a recall . This problem is caused by a design defect and is a safety hazard and should be fixed by BMW. The consumer cost is in the high hundreds of dollars. There is a service bulletin that describes the problem https://static. Nhtsa. Gov/odi/tsbs/2017/mc-10136736-9999. Pdf.