As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT RETURNED FROM AN MOC FLIGHT FOLLOWING A 300 HOUR / 12 MONTH INSPECTION AND UPON SHUTDOWN, THE PILOT NOTICED THAT THE UPPER PLANETARY GEAR OF THE MAIN TRANSMISSION CHIP LIGHT HAD ILLUMINATED. DURING TROUBLESHOOTING IT WAS FOUND THAT THE DEBRIS COLLECTION PAN ON THE INSIDE OF THE TRANSMISSION WAS CRACKED CAUSING IT TO MOVE AND CONTACT THE CHIP DETECTOR WHICH TRIPPED THE UPPER PLANETARY WARNING LIGHT.