Depending on the car, how you disable it may not really disable it at all. Connecting your phone via Bluetooth or taking the car in for service will often let the car upload a backlog of data.
You generally have to completely remove the power from the DCU - which can have as many as three different power sources (including a backup battery with days of power in some cases!), and often disables features in your car like the hands free microphone, built in gps, etc.
You generally have to completely remove the power from the DCU - which can have as many as three different power sources (including a backup battery with days of power in some cases!), and often disables features in your car like the hands free microphone, built in gps, etc.