As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE FLIGHT THE MAIN ROTOR TRANSMISSION LOW OIL PRESS LIGHT ELIMINATED. AN UNSCHEDULED PRECAUTIONARY LANDING WAS MADE IN AN OPEN FIELD WITHOUT INCIDENT. FOLLOWED MM TROUBLESHOOTING PROCEDURES & FOUND THE MAIN ROTOR TRANSMISSION OIL PUMP FAULTY. REPLACED THE MAIN ROTOR TRANSMISSION PUMP WITH A SERVICEABLE UNIT. RETURNED THE ACFT TO SERVICE.