Theory Of Operation

The radio supplies the amplified antenna power circuit with voltage. A 5-volt (GPS/SDARs) signal is transmitted over the center coaxial cable from the radio to the antenna.

Antenna concerns can be diagnosed using special tool #9977-6 or #9977B, Antenna Test Kit. The Antenna Test Kit contains substitute antennas and cables, along with test connectors, that assist in checking the resistance of cables on the vehicle. A