As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) #1 ENGINE FAULT CODE 939 (RGB CHIPS DETECTED) WAS RECEIVED THROUGH THE FAST SYSTEM. MATERIAL WAS ROUTED TO THE LAB AND WAS DETERMINED TO BE M50. FAULT CODE REPEATED THE FOLLOWING DAY AND THE ENGINE WAS REMOVED FROM SERVICE. RGB WILL BE ROUTED TO THE MANUFACTURER FOR REPAIR/INVESTIGATION.FOLLOWING ENGINE REPLACEMENT, THE AIRCRAFT WAS SUBSEQUENTLY RETURNED TO SERVICE. (TC# 20190726023)