Narrative:

Specifically; in our case; one of the amt's test's of the stick-shaker systems revealed that one was inoperative. Granted; this is not a system that is needed often; but when needed; it must operate at 100%. While possibly coincidental; we suspect that other safety systems may have been affected by this status message as well; and that this fault was never discovered or addressed. It concerns us that this fault may have existed the entire time these previous entries were being addressed; and that the aircraft continued to fly while one 'fix' after another failed to correct the problem. The captain contacted maintenance control by phone and expressed his concern regarding the continued flights while accomplishing one fix after another. He also expressed his dissatisfaction with the discovery that the stick-shaker problem was just now discovered; after several previous logbook entries. According to the reaction of the maintenance technician in the cockpit running these tests; the problem was most likely related to the original entry. [Mechanic noted that] he 'accomplished the fault isolation per the fault isolation manual (fim) and replaced the right-hand stall warning module but that did not help. He than troubleshot the wiring per the fim and found diode R843 high resistance and replaced'. The stall warning system operational test was successful.

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Original NASA ASRS Text

Title: Two pilots report about a recurring 'WARN ELEX' EICAS Status message on a B767-300 aircraft that had been written-up and signed-off multiple times without correcting the problem. Aircraft Maintenance Technician (AMT) isolated the fault to a diode with high resistance; but also noted that one of the stick-shakers was probably inoperative the entire time.

Narrative: Specifically; in our case; one of the AMT's test's of the Stick-Shaker Systems revealed that one was inoperative. Granted; this is not a system that is needed often; but when needed; it must operate at 100%. While possibly coincidental; we suspect that other safety systems may have been affected by this status message as well; and that this fault was never discovered or addressed. It concerns us that this fault may have existed the entire time these previous entries were being addressed; and that the aircraft continued to fly while one 'fix' after another failed to correct the problem. The Captain contacted Maintenance Control by phone and expressed his concern regarding the continued flights while accomplishing one fix after another. He also expressed his dissatisfaction with the discovery that the stick-shaker problem was just now discovered; after several previous logbook entries. According to the reaction of the Maintenance Technician in the cockpit running these tests; the problem was most likely related to the original entry. [Mechanic noted that] he 'accomplished the Fault Isolation per the Fault Isolation Manual (FIM) and replaced the Right-Hand Stall Warning Module but that did not help. He than troubleshot the wiring per the FIM and found Diode R843 high resistance and replaced'. The Stall Warning System Operational Test was successful.

Data retrieved from NASA's ASRS site as of July 2013 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.