Narrative:

We were at 2000 ft MSL on a visual to runway 16L at smf during day VMC. Winds were out of the south at 14 KTS. We were configured with flaps 5 degrees and the gear was up. Approaching 1 DOT below GS; I called for gear down and flaps to 15 degrees. At approximately 1500 ft MSL I called for flaps 30 degrees and the before landing checklists. As I looked at the gear/flap indicators; I noticed that there were neither green nor red lights illuminated for the gear. I brought this to the captain's attention and he performed a 'ptt' on the lights. None of the lights illuminated. We performed a low approach at 500 ft AGL and tower said our gear appeared down. We did a go around and were given a climb to 2000 ft MSL and a turn to the north. We left the gear down and the flaps at 15 degrees. With the autoplt engaged; the captain took control of the aircraft and I confirmed that the gear was down and locked by viewing them through the viewing ports. After I strapped back inyo my seat; we ran the QRH and found the 'section 5' circuit breaker behind my seat was popped. After resetting the circuit breaker; we immediately noticed 3 green lights. Once all QRH procedures were complete; I was given control of the aircraft back. We proceeded to get vectors for another visual approach to runway 16L. The rest of the approach and landing were uneventful.

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Original NASA ASRS Text

Title: A B737-300 FLT CREW ON FINAL APCH EXTENDED THE LNDG GEAR AND HAD NO LNDG GEAR SAFE OR UNSAFE LIGHTS. CREW DISCOVERED AN OPEN CIRCUIT BREAKER.

Narrative: WE WERE AT 2000 FT MSL ON A VISUAL TO RWY 16L AT SMF DURING DAY VMC. WINDS WERE OUT OF THE S AT 14 KTS. WE WERE CONFIGURED WITH FLAPS 5 DEGS AND THE GEAR WAS UP. APCHING 1 DOT BELOW GS; I CALLED FOR GEAR DOWN AND FLAPS TO 15 DEGS. AT APPROX 1500 FT MSL I CALLED FOR FLAPS 30 DEGS AND THE BEFORE LNDG CHKLISTS. AS I LOOKED AT THE GEAR/FLAP INDICATORS; I NOTICED THAT THERE WERE NEITHER GREEN NOR RED LIGHTS ILLUMINATED FOR THE GEAR. I BROUGHT THIS TO THE CAPT'S ATTN AND HE PERFORMED A 'PTT' ON THE LIGHTS. NONE OF THE LIGHTS ILLUMINATED. WE PERFORMED A LOW APCH AT 500 FT AGL AND TWR SAID OUR GEAR APPEARED DOWN. WE DID A GAR AND WERE GIVEN A CLB TO 2000 FT MSL AND A TURN TO THE N. WE LEFT THE GEAR DOWN AND THE FLAPS AT 15 DEGS. WITH THE AUTOPLT ENGAGED; THE CAPT TOOK CTL OF THE ACFT AND I CONFIRMED THAT THE GEAR WAS DOWN AND LOCKED BY VIEWING THEM THROUGH THE VIEWING PORTS. AFTER I STRAPPED BACK INYO MY SEAT; WE RAN THE QRH AND FOUND THE 'SECTION 5' CIRCUIT BREAKER BEHIND MY SEAT WAS POPPED. AFTER RESETTING THE CIRCUIT BREAKER; WE IMMEDIATELY NOTICED 3 GREEN LIGHTS. ONCE ALL QRH PROCS WERE COMPLETE; I WAS GIVEN CTL OF THE ACFT BACK. WE PROCEEDED TO GET VECTORS FOR ANOTHER VISUAL APCH TO RWY 16L. THE REST OF THE APCH AND LNDG WERE UNEVENTFUL.

Data retrieved from NASA's ASRS site as of January 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.