Grundig Emden radio 111035103a VW Beetle

Vintage Grundig Emden radio for VW Beetle in used condition and not working. The radio is marked with "VW 111 035 103A GRUNDiG EMDEN III”. I put power on it and the on/off knob is working and also the power light bulb is burning. After that I found out, that the right knob, the frequency selector, has no function. You see nothing moving, when you turn the frequency selector knob. So I stopped testing. The chrome face plate has no dents and is very good after polish. The VW knobs are original and also very good. The radio itself has also no damages. Made in Germany for VW Beetle.