As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) ACFT RETURNED TO BASE AFTER THE ODOR OF SMOKE WAS DISCOVERED IN THE COCKPIT. UPON INSPECTION, IT WAS DISCOVERED THAT THE PILOTS RMI INTERNAL LIGHTING HAD FAILED, WHEN THE LIGHTING FAILED THE 1 AMP CIRCUIT BREAKER DID NOT POP, ALLOWING THE UNIT TO HEAT UP, CAUSING THE ODOR. THE RMI WAS REPLACED AND THE C/B WAS REPLACED.