I've tried a couple of different places, but the HSI won't recognise any VOR or LOC, The autopilot descends through the set altitude, yet levels out fine when ascending. With the radio NAV mode not functioning, selection of APP doesn't have any effect either.What needs changing to get these basic IFR instruments to function properly? (At all)Cheers

I haven't experienced these problems. The AP does sometimes bust the set altitude a bit but then recovers to attain the setting...and I've been able to capture localizer and glide slope with no problem (although sometimes it seems to fly a bit high on the GS). I ususally set the VOR and LOC/ILS freqs within the Garmin, rather than the radios themselves.

Thanks for that insight, I found the frequencies entered via the GPS do the trick nicely.