I have a 98 grand cherokee 4.0. It came with a chrysler CD changer in the storage area. The am/fm factory radio quit playing fm. Behind the instrument panel is what looks like a fm modulator. I guess the modulator takes the cd signal and plays it through the radio on a certain channel. If this modulator is bad, would it kill the fm portion of the radio? It still plays am.

 

check the connection on the antenna wire where it comes in from the antenna and goes to the radio. there is a spring loaded clip on most that goes bad. the fix is to remove the spring and reconnect w/ electrical tape.