Narrative:

While climbing out on flight xyz from service to abq, the cabin door annunciator illuminated. Per our emergency procedures, we declared an emergency and returned to service. After landing, we checked the security of the cabin door and found it to be secure. The cabin door annunciator extinguished. After talking with our company maintenance control, we determined the cause to be a faulty microswitch in the cabin door annunciator system. We wrote up the discrepancy and deferred it under our MEL for the cabin door annunciator. We then refiled our flight plan, received a new release from our dispatch, and continued operations without further incident.

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Original NASA ASRS Text

Title: A BEECH 02 IN CLB AT FL180 DECLARED AN EMER AND DIVERTED DUE TO A CABIN DOOR WARNING CAUSED BY A FAULTY DOOR LOCK SENSOR.

Narrative: WHILE CLBING OUT ON FLT XYZ FROM SVC TO ABQ, THE CABIN DOOR ANNUNCIATOR ILLUMINATED. PER OUR EMER PROCS, WE DECLARED AN EMER AND RETURNED TO SVC. AFTER LNDG, WE CHKED THE SECURITY OF THE CABIN DOOR AND FOUND IT TO BE SECURE. THE CABIN DOOR ANNUNCIATOR EXTINGUISHED. AFTER TALKING WITH OUR COMPANY MAINT CTL, WE DETERMINED THE CAUSE TO BE A FAULTY MICROSWITCH IN THE CABIN DOOR ANNUNCIATOR SYS. WE WROTE UP THE DISCREPANCY AND DEFERRED IT UNDER OUR MEL FOR THE CABIN DOOR ANNUNCIATOR. WE THEN REFILED OUR FLT PLAN, RECEIVED A NEW RELEASE FROM OUR DISPATCH, AND CONTINUED OPS WITHOUT FURTHER INCIDENT.

Data retrieved from NASA's ASRS site as of July 2007 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.