The SDARS is a separate tuner for digital reception. SDARS receives the data in terrestrial form or via satellite. Two aerials are fitted for reception. One aerial is for terrestrial reception another aerial is for digital reception.
If the satellite reception is disrupted, SDARS automatically switches to AM/FM reception. The loss of quality between digital radio and the standard AM/FM radio can be heard clearly.
Digital radio means that a much higher number of stations can be picked up. In addition to the audio data, other information is also broadcast. The sound quality is close to that of a CD or MD.
If the satellite radio optional extra is fitted, the AM/FM receiver is decoded in the headunit. In this case, the SDARS is controlled via the MOST bus by the headunit (radio/M-ASK/CCC).
To enable AM/FM and satellite reception, two aerials are connected to the SDARS.