As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON APPROACH TO DRO WHEN GEAR WAS EXTENED. 3 GREENS WOULD NOT ILLUM LANDING GEAR IND C.B. POPPED GREEN NOTIFIED. MX CTRL ADVISED TO RETURN TO FMN. AIRCRAFT THEN RETURNED TO FMN DECLARED EMERGENCY AND LANDED WITH NO FURTHER INCIDENT. R & R ANNUNCIATOR PWR SOURCE PCB & WIRES ON HARN. P/N 129-364079-7. S/N 842A93