As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT CREW EXECUTED AN AIRBORNE RETURN DUE TO A BURNING ODOR IN THE COCKPIT. CREW REPORTED THE LOSS OF THE F/O'S FD ALONG WITH E8 CIRCUIT BREAKER TRIPPED. MX COMPLIED WITH CABIN SMOKE/ODOR TROUBLESHOOTING CARD 2120-2367. FOUND F/O'S FMA WITH BURNED ODOR. REPLACED F/O'S FMA, PERFORMED RTS DFGC 1 AND 2 BOTH CHECKED GO.