BMW F10 key not recognised or battery drains quickly
How do I start the F10 when the key is not recognised?
Hold the key against the side of the steering column and start the car with the start button. The doors can be opened with the key's mechanical spare blade. This is a temporary workaround, not a repair.
Why does the F10/F11 key battery drain quickly?
The cause can be a broken comfort access door handle, a damp key or a button that stays pressed in a pocket. A cheap charger plugged into the cigarette lighter has also interfered with the key's signal. If the doors only lock from a distance, the handle may be broken.
What fault can be behind the key not being recognised?
Often it is the remote control receiver, which is integrated into the diversity antenna. A pin in the receiver's wiring connector can oxidise, in which case operation returns for a while when the connector is unplugged. The codes show on a diagnostic tool; let a workshop find the fault.