3363782 - E3510 RADIO - Functional description (Hi-Fi system)

Functional description

The radio P20 is supplied directly (7 of connector A) from the battery via the line of fuse F39 of the unit under the dashboard B2 . Pin 4 of connector A receives a supply from the INT line protected by fuse 49 of control unit B2 . Pins 1 and 3 of connector A receive the CAN line with which the radio P20 is connected to the Body Computer M1 and the other nodes of the system. Pin 8 of connector A is earthed. The aerial P25 is connected to the radio also via the specific coaxial cable.

The cables with the signals to the loudspeakers com out of connector B; these signals are sent to the amplifier P70, which controls the loudspeakers:

• pins 5 and 6 to left front loudspeakers P35 and P45 ,
• pins 3 and 4 to right front loudspeakers P35 and P46 ,
• pins 7 and 8 to left rear loudspeakers P30 and P47 ,
• pins 1 and 2 to right rear loudspeakers P31 and P48 ,

Radio P20 is not connected to the radio controls on the steering wheel: the connection is via the clock spring D47 , which is a node of the CAN network.  See E1050  CAN CONNECTION LINES The amplifier P70 is supplied directly from the battery to pins C8 - through the line of fuse 54 of boot compartment fuse box B45 ; It is then connected - pin C2 - via a specific line to the radio P20 - pin 6 of connector C - which sends the signal to switch on the amplifier. Another line connects amplifier P70 - pin C3 - to radio P20 - pin 26 of connector A - and informs the radio of the presence of the amplifier. Pin C1 of amplifier P70 to earth. The other signals coming from the BOSE amplifier P70 control, as described above, the loudspeakers of the basic system. The unit containing amplifier P70 also contains rear subwoofer P49 .