[W126 Coupe] antenna mast replacement problem

[Thomas Oelsner]

I'm trying to replace my Hirschmann mast, which does not extend beyond 6". I
have loosened the nut, had somebody turn on the radio  while I have
pulled..HARD. The nylon will not disengage, only uncoiling about 6". I have
tried cycling by turning the radio on and off. Nothing works. I am beginning
to wonder if not only the mast is a problem, but the motor itself as it only
appears to turn on for about 5-6 seconds. Anybody have any thoughts for
further troubleshooting/replacement? I'm hoping I don't need to replace the
entire unit.

Tom Oelsner