Radio P20 is supplied directly (pin 7 of connector A) from the battery via the line of fuse F39 of the junction unit under the dashboard B2 .The radio P20 receives an ignition-operated (INT) power supply (pin 4 of connector A) via the line for fuse F51 of the junction unit under the dashboard B2 .Pin 8 of connector A is earthed.Pins 1 and 3 of connector A receive the CAN line by which the radio P20 is connected to the Body Computer M1 and the other system nodes.The Body Computer M1 is connected to the radio controls on the steering wheel via clock spring D47: pin 27 of connector H of M1 receives the signals for the buttons on the right of the steering wheel, whilst pin 15 of connector H of M1 receives the signals from the buttons on the left of the steering wheel.The Body Computer M1 receives a direct supply from the battery via the line protected by maxifuse B99 at pin 18 of connector F of the interface with the junction unit under the dashboard B2; the ignition-controlled supply (INT) reaches pin 9 of connector F of the interface with the junction unit B2.