BMW E46 remote key battery and re-programming
Does the E46 key need re-programming after replacing the remote battery?
Usually not. The battery can be replaced without re-programming. If the replacement takes a long time, the key may be forgotten, and then it has to be re-programmed. The battery is a CR2016 (3 V).
How do you program the remote to the E46?
1. Close the driver's door, turn the ignition key to position 1 for no more than 5 s, back to position 0 and pull the key out. 2. Press the unlock button and hold it down. 3. Press the lock button three times within 10 s. 4. Release the unlock button. The LED flashes slowly and the central locking locks and unlocks once when programming has succeeded. 5. Program the other keys within 30 s by repeating steps 2-4.
Why does the other key stop working when I program one?
All keys must be programmed in the same session, with no more than 30 s between them. Programming another key separately can silence the first one. Also do not put the other key in the ignition during programming.