Narrative:

Lav smoke master warning message presented on EICAS just before leveling at cruise altitude of 12;000 feet. The pilot flying took over radios as I ran the QRH for the lav smoke master caution message. We completed the QRH checklist and the EICAS message was no longer present at the conclusion of the checklist. When we established crew communication per the QRH checklist the flight attendant advised us there was no indication of smoke or fire in the lavatory but that the passengers were complaining of heat and an odor in the cabin. We began to run the smoke evacuation checklist and asked the flight attendant if the odor required evacuation. We were told no. We chose to land at the nearest suitable airport.the approach was standard and we advised arff (aircraft rescue and firefighting) that we would stop on the runway and they would confirm that the outside of the aircraft did not exhibit any signs of smoke or fire. We were advised that the aircraft had no visible signs of smoke or fire. I asked the flight attendant if the cabin was safe to taxi and there were no signs of smoke or fire in the cabin. Tower gave us taxi instructions and we continued to the gate were arff inspected the aircraft again for any visible signs of smoke or fire. There were no signs and we deplaned the passengers in a standard fashion. Caused by an indication of lav smoke on the EICAS and corresponding master warning.handed the radio duties to the pilot flying (PF) and ran the lav smoke QRH. My initial reaction was to treat the indication as a valid indication of smoke or fire in the lavatory.

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Original NASA ASRS Text

Title: Embraer ERJ-145 flight crew reported cockpit indications of lavatory smoke; which could not be verified; however a diversion to a nearby suitable airport was initiated.

Narrative: LAV SMOKE master warning message presented on EICAS just before leveling at cruise altitude of 12;000 feet. The Pilot Flying took over radios as I ran the QRH for the LAV SMOKE Master Caution Message. We completed the QRH Checklist and the EICAS Message was no longer present at the conclusion of the checklist. When we established crew communication per the QRH checklist the flight attendant advised us there was no indication of smoke or fire in the lavatory but that the passengers were complaining of heat and an odor in the cabin. We began to run the SMOKE EVACUATION Checklist and asked the Flight Attendant if the odor required evacuation. We were told no. We chose to land at the nearest suitable airport.The approach was standard and we advised ARFF (Aircraft Rescue and Firefighting) that we would stop on the runway and they would confirm that the outside of the aircraft did not exhibit any signs of smoke or fire. We were advised that the aircraft had no visible signs of smoke or fire. I asked the flight attendant if the cabin was safe to taxi and there were no signs of smoke or fire in the cabin. Tower gave us taxi instructions and we continued to the gate were ARFF inspected the aircraft again for any visible signs of smoke or fire. There were no signs and we deplaned the passengers in a standard fashion. Caused by an indication of LAV SMOKE on the EICAS and corresponding Master Warning.Handed the radio duties to the Pilot Flying (PF) and ran the LAV SMOKE QRH. My initial reaction was to treat the indication as a valid indication of smoke or fire in the lavatory.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.