What was found
D: ON TAXI OUT WE STARTED GETTING A STRONG SMELL IN THE COCKPIT AND IN THE REST OF THE AIRPLANE OF SOMETHING BURNING. WE STARTED LOOKING AT THE ELECTRICAL PAGE AND FOUND NOTHING. A REMOTE CB WAS TRIPPED, LH RECIRC FAN. THEN SENT HAS CONTINUED TO STAY IN THE AIRPLANE UNTIL WE GOT BACK TO THE GATE AND OPENED DOORS AND WINDOWS. / C: TROUBLESHOT ELECTRICAL SMOKE SMELL, CMC FLAGGING FAULT CODE: 21240008AM2 AND 21245800AM1 LH RECIRC FAN. NO SMOKE CAUTION MESSAGES OR SMOKE WARNING MESSAGES NOTED ON EICAS. ONLY CB ADVISORY MESSAGE NOTED ON EICAS. AS REPORTED BY THE PILOT, A REMOTE CB WAS TRIPPED (LH RECIRC FAN). DEFERRED LH RECIRC FAN PER MEL 21-24-1A. MX ACTION COMPLETE. PLACARD INSTALLED. ALSO, COMPLIED WITH ABNORMAL SMOKE SMELL IN THE CABIN/COCKPIT REF FIM 21-20-00-810-801-A. RAN BOTH PACKS FOR 15 MINUTES MINIMUM TO AIR OUT THE CABIN/COCKPIT AND OPENED WINDOWS TO VENT OUT SMELL. NO ELECTRICAL SMELL NOTED AT THIS TIME. ONE PRIOR PAX INDUCED SMOKE EVENT NOTED FROM THE AFT LAV SMOKE DETECTOR ON 10/3/22. NOOCT 05, 2022 STATION: YYZ--TROUBLESHOT ELECTRICAL SMOKE SMELL, CMC FLAGGING FAULT CODE: 21240008AM2 AND 21245800AM1 LH RECIRC FAN. NO SMOKE CAUTION MESSAGES OR SMOKE WARNING MESSAGES NOTED ON EICAS. ONLY CB ADVISORY MESSAGE NOTED ON EICAS. AS REPORTED BY THE PILOT, A REMOTE CB WAS TRIPPED (LH RECIRC FAN). DEFERRED LH RECIRC FAN PER MEL 21-24-1A. MX ACTION COMPLETE. PLACARD INSTALLED. ALSO, COMPLIED WITH ABNORMAL SMOKE SMELL IN THE CABIN/COCKPIT REF FIM 21-20-00-810-801-A. RAN BOTH PACKS FOR 15 MINUTES MINIMUM TO AIR OUT THE CABIN/COCKPIT AND OPENED WINDOWS/DOORS TO VENT OUT SMELL. NO ELECTRICAL SMELL NOTED AT THIS TIME. ONE PRIOR PAX INDUCED SMOKE EVENT NOTED FROM THE AFT LAV SMOKE DETECTOR ON 10/3/22. NO OTHER EVENTS NOTED. AIRCRAFT OK FOR SERVICE.