What was found
ON SHORT FINAL TO THE HOSPITAL THE PILOT HAD A TRANSMISSION OIL PRESSURE WARNING LIGHT ILLUMINATE ON THE CAUTION WARNING PANEL. HE DECIDED TO DIVERT TO THE LOCAL AIRPORT, WHERE HE LANDED WITHOUT INCIDENT WITH A PATIENT ONBOARD, WHICH WAS TRANSPORTED BY GROUND. THE MECHANIC TROUBLESHOT THE SYSTEM AND DID A 20 MINUTE GROUND RUN WITHOUT FURTHER INDICATION. THE ACFT WAS GOING TO RETURN TO THE BASE AND WHEN THE PILOT RAN THE ACFT UP AND PICKED IT UP TO A HOVER THE TRANSMISSION OIL PRESSURE WARNING LIGHT FLICKERED. THE ACFT WAS FURTHER TROUBLESHOT AND WAS DETERMINED THAT THE OIL PRESSURE SWITCH WAS INOP. TRANSMISSION OIL PRESSURE SWITCH WAS REPLACED ON 8-13-17 WITH A SATISFACTORY CHECK F