Originally Posted by jmh
As has been mentioned it just plugs into the OBD port under the dash (comes with the cable/connector) . You store the small control unit inside the dashboard and route the cable to the OBD port. It can be simply unplugged for service/coding etc .
Also no battery draw when the car is turned (other gauges did draw power and left you with an empty battery)
More details on the BMW install can be found at
I have the P3 gauge in my M5 since last year without any problems/issues
I have an extra "analog" boost sensor that can be used if you go crazy with modifications.
Otherwise, as jmh said, everything goes across the Flexray bus.