Mystery ticking from radio
 

When I tried to turn on the radio on my 1984 380sl, the radio would not come on and there was a ticking sound coming from the radio when I held the on button on. Anyone out there have any ideas or thoughts?

Eons ago, such a sound might be coming from the ignition system. Typically, a loose spark plug wire. Does the sound increase in rate when you press the gas? Resistor plugs pretty much eliminated this problem.

check your ground wire for the radio

The noise you are probably hearing is the cassette player flywheel turning making the ticking noise. Needless to say the radio will not come on as the player thinks for some reason the cassette is playing...There may be something stuck in the tape path...Disassembly may yield the answer.