Aerial Diagnosis

Aerial diversity is a system that selects the aerial that has the best reception from aerials in the vehicle (max.4). This signal is reinforced in the aerial diversity and transmitted to the tuner. In the following, the tests preformed in the aerial diversity procedure are briefly described. Depending on the equipment, it is possible that aerial diversity is not fitted. In this case, the aerial is directly connected to the headunit via an aerial amplifier.

DC measurement

The DC measurement detects whether the aerial diversity is correctly connected to the tuner. Additionally, the corresponding fault code entries will also be evaluated during the procedure.
The diversity function and the aerial connection will be checked by means of the aerial self-diagnosis. However, these results are not always significant. In this case, it is necessary to consider the field strength of the transmitter that can be received.

Service mode

In the radio service mode, it is possible to display the quality and the field strength of the radio station already being received (not MASK and CCC). The values displayed are between 0 and 15.

• 15 corresponds to a very good reception
• 0 corresponds to a very bad reception

Proceed as follows to call up the service mode :

• Terminal 30g ON
• Switch off the radio
• Switch on the radio again
• Within 8s and for a duration of 8s, press the button for the manual search
• The radio switches into the Service mode.

 Evaluation

If the result of the aerial diversity self-diagnosis is OK, the field strength of the transmitter already received can be displayed in the procedure.
If an aerial has a noticeably weaker reception than the other aerials, the vehicle must be turned around by 90 degrees and the measurement taken again. If a weakness in the tolerance range continuous to occur, then at least one FM aerial is faulty. The faulty FM aerial must be checked.