As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 2873, EWR-LAX. EMRGENCY DECLARED. SMOKEY SMELL IN COCKPIT 13000FT IN AIR FOLLOWED BY HUMMING NOISE IN AVIONICS BAY FOLLOWED BY SILENCE. SMELL OF SMOKE DISSAPATED AFTER APPROX 5 MIN AND VENT EXTRACT ECCAM ILLUMINATED; R & R AVIONICS FAN REF AMM 21-26-00. R&R AIR FILTER REF AMM 21-50-00. NO SMELL NOTED. OPS CHK OK.