[Matthewts]

Depends on a few things like if they are factory or aftermarket. . . Some of the factory installed units were installed with an fm transmitter. If this is the case you will easily see it in the console and you can see what frequency it is transmitting the sound on. . . Otherwise if it is a factory setup you should have some headphones that will pick up the sound at close range (like sitting in the seat). . . If it is aftermarket . . . let the trouble shooting begin