Intelligent alternator control
Charges the battery mainly when it costs the engine least.
In the alternator and DME software, with the battery sensor on the negative terminal.
Charging is reduced under acceleration and increased while coasting or braking to save fuel.
Filling a water tank when the water is free.
Charging warnings, a flat battery or flickering lights can involve the alternator, battery sensor or registration.
Batteries and connections depend on age, charging and usage. Control units are diagnosed by faults, power and communications.
A fuse or connection differs from a coded controller. Identify the cause before replacing an expensive electronic module.
After a battery change, BMW systems usually need the new battery registered so charging matches its age.
BMW low-voltage systems across combustion, hybrid and electric models; equipment varies.