E-brake caused limp mode

[ejakobitz]

Hello all. My name is Eddie and I purchased a 2012 BMW Z4 with 27,000 miles on it about 6 months ago. I'm having a lot of fun with the car. I'm curious if anyone has experienced anything like I did yesterday. I was driving with a passenger who was fumbling around and pulled the E-brake while I was accelerating away from a stop light. I estimate that I was going about 40 when he pulled the E-brake. The brake worked as designed and brought the car down to nearly a stop but then the car went into limp mode. I slowly drove it off to a side road and parked and ensured that the brake was off but the car remained in limp mode. I turned it off for a minute and turned it back on and all was fine. It drove home as though nothing was wrong. I checked for any codes using a code reader as well as the code viewer on the dash and there were 0 codes. Everything seems fine. Has anyone else experienced anything like this? I'm just kind of curious about.

[ejakobitz]

Just one additional note, the e-brake on the 2012's is an electronic e-brake and not the old style hand brake. Sorry if everyone knows that already. I wasn't sure when the electric version came out.

[B21]

Welcome…all E89s were built with electronic parking brake.

It’s probable that the some part of the circuitry got warm and/or there’s a protection logic in place following deployment in that manner.

If all works ok now and no codes then it’s probably ok.

A professional coding system like ISTA would show the history of this event.

[ejakobitz]

Thanks B21. I was hoping/suspecting that that was the case. Thanks for the info.

[Bob20124]

Applying the E-brake during acceleration caused an extremely high load on the engine. This probably exceeded safety parameters and caused limp mode. As B21 stated, if limp mode cleared after restart you should be ok.