Does an electrical system reset also reset the aftermarket tune?

[rated_m3]

Just wondering, because I’m having some work done to the car and I don’t want to reset my BPM tune to the factory tune. What exactly involves an electrical system reset? Does the car need to be flashed or just a battery reset?

[dpaul]

Not sure there is a definitive answer - "electrical system reset" is not a procedure described by BMW.

Individual modules (module = DME, CAS, CIC etc) can be reset - here 'reset' is an officially documented term - using BMW diagnostic software like NCSExpert or Tool32. This form of resetting does not change program or parameter data i.e. it does not overwrite current program or parameter code. It is most analogous to a computer reboot.

So if this is what you are talking about, it's not going to affect your BPM tune, any more than disconnecting and reconnecting the battery would.

The only thing that would affect your tune would a module update in which the DME parameter code is re-flashed. That might happen if a dealer determines you have modules whose program/parameter code is not the current version specified for your vehicle.

I guess you want to ask your service personnel exactly what they mean by "electrical system reset". I'll bet they mean disconnecting the battery for 20 minutes.

[rated_m3]

Thanks I’ll keep that in mind.