Will not catch GS on Fokker100 Project?

Hi there.I can't figure out why the fokker project and thir plane 70 and 100 won't track the GS. If anybody have a suggestio then please advice.1. The button for ILS-intercepting will not tun on. I can hear the click but there is no light in the button.2. Radio and freq turn on and set3. The instrument show that it is recieving the ILS and showing the DME distance.4. I have downloade the new updated fokker panel from fokker projectWhy wont the AP catch the GS? Walle