As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE, POWERPLANT MESSAGE APPEARED ON ED. RETURNED TO FIELD, LANDING UNEVENTFUL. INTERROGATED CDS FOUND FAULT CODE 120,122,AND 134 B ON NR 1 PROP. C/W FIM TASK 61-20-03-810-817. CLEARED AND GROUND RAN NR 1 ENGINE TWICE. NO DEFECTS NOTED. NO POWERPLANT MESSAGE NOTE. RETURNED TO SERVICE.