Diversity Antenna System

This vehicle has a scanning diversity AM/FM antenna system. This system consists of the following parts:

1. 3 Antenna Grid Patterns on the rear window interfacing with the rear defog grid.
2. AM/FM Antenna Module
3. Coax - The radio sends a 12 volt signal to module when in FM mode (less than 1 volt in AM and WX mode). The radio also sends feedback on signal quality to module in FM mode.
4. 12V power feed from the Radio to the Antenna Module 0.35 pink wire with single pin connector. The 12V power feed from the radio to the AM/FM antenna module is on any time the radio is on.
5. Radio

In AM and WX mode the system functions as follows:

The AM/FM antenna module takes the signal from only the AM/FM1 antenna pattern on the rear window. The AM/FM antenna module amplifies this signal and sends it to the radio. In this mode the radio does not supply any voltage to the center conductor of the coax and there is no feedback signal present on the coax.

In FM mode the system functions as follows:

The AM/FM antenna module takes the best signal from one of the three (3) FM antenna patterns on the rear window. The AM/FM antenna module amplifies this signal and sends it to the radio. In this mode the radio supplies 12V to the center conductor of the coax and this switches the module into FM mode. The radio also supplies a feedback signal, along the coax, to the AM/FM antenna module, which indicates the quality of the signal. Based on measured input signal level and the feedback from the radio the AM/FM antenna module switches between the 3 antennas to find the best signal.