Narrative:

We were vectored to the final approach course. At the marker I called for gear down; condition levers maximum. We both noticed that the left main gear down light failed to illuminate. Considering our present position and lack of available time to troubleshoot; we called for a missed approach and followed ATC instructions; cleaned up the aircraft and requested time to run the QRH. The PNF then performed the gear unsafe QRH. At that time; determined that the lamps had failed; swapped lamps and all seemed in order. We then requested ATC for sequence back to the final approach course. We decided to initiate the gear down sequence early in order to better observe the operation and possibly continue the QRH. The same indicator failed to illuminate. The PNF cycled the gear per QRH; observed that the in-transit light failed to illuminate on the gear up; but illuminated on the gear down sequence. At that point we made the decision that the in-transit light was not functioning properly; which the QRH directed us to the emergency landing section. PNF called ATC; requested another missed approach; declared an emergency; and to vector us around again to the final approach course for an emergency landing. The PNF performed the QRH; communicated with the flight attendant and passenger. By that time; we had been vectored back to the final approach course. Controls were exchanged and I continued with the rest of the QRH. On short final; an aircraft holding short of runway indicated that the left main was indeed down. After touchdown; the landing roll continued until we slowed to a speed where we exited the runway onto the deice pad. Waited at that location until maintenance could determine that status of the gear and then decide a course of action. All gear was pinned; maintenance told us it was an indication fault; the gear was safe so we taxied under our own power back to the gate. Failed to get a left main gear lock indication which was not associated with a bad lamp. Supplemental information from acn 786167: I declared an emergency at this point and told ATC we wanted to have vectors close to the airport to run all the QRH items required. While on vectors I ran the emergency checklist; talked to flight attendant; and passenger. When I was finished; I took control of the aircraft and asked the first officer to do PNF duties and continue the emergency checklist. The problem was in the relay.

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Original NASA ASRS Text

Title: SF340 FLT CREW HAS A LEFT MAIN GEAR INDICATION FAILURE ON APPROACH THAT WAS NOT ASSOCIATED WITH A BAD LAMP. AFTER TWO MISSED APPROACHES AND TROUBLESHOOTING; AN UNEVENTFUL LANDING RESULTED.

Narrative: WE WERE VECTORED TO THE FINAL APCH COURSE. AT THE MARKER I CALLED FOR GEAR DOWN; CONDITION LEVERS MAX. WE BOTH NOTICED THAT THE L MAIN GEAR DOWN LIGHT FAILED TO ILLUMINATE. CONSIDERING OUR PRESENT POS AND LACK OF AVAILABLE TIME TO TROUBLESHOOT; WE CALLED FOR A MISSED APCH AND FOLLOWED ATC INSTRUCTIONS; CLEANED UP THE ACFT AND REQUESTED TIME TO RUN THE QRH. THE PNF THEN PERFORMED THE GEAR UNSAFE QRH. AT THAT TIME; DETERMINED THAT THE LAMPS HAD FAILED; SWAPPED LAMPS AND ALL SEEMED IN ORDER. WE THEN REQUESTED ATC FOR SEQUENCE BACK TO THE FINAL APCH COURSE. WE DECIDED TO INITIATE THE GEAR DOWN SEQUENCE EARLY IN ORDER TO BETTER OBSERVE THE OP AND POSSIBLY CONTINUE THE QRH. THE SAME INDICATOR FAILED TO ILLUMINATE. THE PNF CYCLED THE GEAR PER QRH; OBSERVED THAT THE IN-TRANSIT LIGHT FAILED TO ILLUMINATE ON THE GEAR UP; BUT ILLUMINATED ON THE GEAR DOWN SEQUENCE. AT THAT POINT WE MADE THE DECISION THAT THE IN-TRANSIT LIGHT WAS NOT FUNCTIONING PROPERLY; WHICH THE QRH DIRECTED US TO THE EMER LNDG SECTION. PNF CALLED ATC; REQUESTED ANOTHER MISSED APCH; DECLARED AN EMER; AND TO VECTOR US AROUND AGAIN TO THE FINAL APCH COURSE FOR AN EMER LNDG. THE PNF PERFORMED THE QRH; COMMUNICATED WITH THE FLT ATTENDANT AND PAX. BY THAT TIME; WE HAD BEEN VECTORED BACK TO THE FINAL APCH COURSE. CTLS WERE EXCHANGED AND I CONTINUED WITH THE REST OF THE QRH. ON SHORT FINAL; AN ACFT HOLDING SHORT OF RWY INDICATED THAT THE L MAIN WAS INDEED DOWN. AFTER TOUCHDOWN; THE LNDG ROLL CONTINUED UNTIL WE SLOWED TO A SPD WHERE WE EXITED THE RWY ONTO THE DEICE PAD. WAITED AT THAT LOCATION UNTIL MAINT COULD DETERMINE THAT STATUS OF THE GEAR AND THEN DECIDE A COURSE OF ACTION. ALL GEAR WAS PINNED; MAINT TOLD US IT WAS AN INDICATION FAULT; THE GEAR WAS SAFE SO WE TAXIED UNDER OUR OWN PWR BACK TO THE GATE. FAILED TO GET A L MAIN GEAR LOCK INDICATION WHICH WAS NOT ASSOCIATED WITH A BAD LAMP. SUPPLEMENTAL INFO FROM ACN 786167: I DECLARED AN EMER AT THIS POINT AND TOLD ATC WE WANTED TO HAVE VECTORS CLOSE TO THE ARPT TO RUN ALL THE QRH ITEMS REQUIRED. WHILE ON VECTORS I RAN THE EMER CHKLIST; TALKED TO FLT ATTENDANT; AND PAX. WHEN I WAS FINISHED; I TOOK CTL OF THE ACFT AND ASKED THE FO TO DO PNF DUTIES AND CONTINUE THE EMER CHKLIST. THE PROB WAS IN THE RELAY.

Data retrieved from NASA's ASRS site as of May 2009 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.