Tried to start my M3W today for first time since last Nov. Brutal winter this year and stored in unheated garage. Despite using a battery tender battery didn’t have enough charge to turn her over. Time for new battery. The battery is still supplying some charge to the ECU. Any problem with completely disconecting the ECU from power during battery change in the M3W?
2015 M3W, Morgan Aero Racing Stage 1, Garage 56 Stage 2, sport black, saddle tan, jeweled SS dash.
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