Narrative:

During cruise flight we received a 'left jet ovht fail' caution message. The QRH directs you to move the fire detection test switch to 'warn'. If no 'left jetpipe ovht' warning message appears; the QRH states that fire detection is not available and to land at the nearest suitable airport. We diverted to ZZZ; executed a normal landing; entered the discrepancy in the aml and turned the aircraft over to maintenance.

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Original NASA ASRS Text

Title: The Flight Crew of an A319 aircraft diverted to the nearest suitable airport when the left engine fire detection system became unavailable.

Narrative: During cruise flight we received a 'L Jet Ovht Fail' Caution message. The QRH directs you to move the Fire Detection Test switch to 'WARN'. If no 'L JETPIPE OVHT' Warning message appears; the QRH states that fire detection is not available and to land at the nearest suitable airport. We diverted to ZZZ; executed a normal landing; entered the discrepancy in the AML and turned the aircraft over to maintenance.

Data retrieved from NASA's ASRS site as of April 2012 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.