I've just purchased a 91' 420 SEL and the radio antennae doesn't go up.

And you can't pull it up by hand either.

The owners manual (radio) mentions a switch that, on some cars, is located above the radio that controls the antennae.
This car has no such switch.

Is there any such switch and, if so, where might it be located?

Or is the problem possibly a bad motor or?

Any thoughts on how to troubleshoot?

Thanks in advance for any help/ideas...