What was found
(CAN) CREW REPORTED BOTH VOR SYSTEMS WERE NOT FUNCTIONING COMPLETELY. VOR AUDIO SIGNAL COULD BE PICKED UP AND TO/FROM FLAG WORKED. INDICATOR NEEDLES WOULD NOT DEVIATE FROM CENTER. COMPONENTS FAILED TO DETERMINE SOURCE OF PROBLEM. A/C WAS SENT TO FACILITY WHERE THEY DETERMINED THAT AUDIO PANEL DID NOT HAVE RELAYS INSTALLED FOR AUTOPILOT. IT WOULD APPEAR THAT AUDIO PANEL WAS DIFFERENT FOR A/C WITH FACTORY INSTALLED AUTOPILOTS. AUDIO PANEL DOES NOT LOOK DIFFERENT FROM FRONT, NO DISTINGUISHING PLACARDS TO WARN THAT UNIT IS FOR AUTOPILOT EQUIPPED MODELS ONLY. ALSO, NONE OF THE UNITS WE TRIED WERE SERIALIZED. RESULT WAS THAT PROPER AUDIO PANEL WAS INSTALLED FOR A/C & ALL RELATED SYSTEMS CHECKED SERVICEABLE.