Functional description, see BMW Service Technology:
TIS -> Document -> SI Technology -> Enter SBT Number
SBT number:
The data interchanged for control of the gearshifts between DME and SMG via the idle actuator / SMG CAN are monitored as regards plausibility. If a fault occurs, this can lie in the CAN bus or can be a secondary fault of a component on the engine or gearbox.