B737 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 239
Aircraft Equipment Problem Less Severe
Flight Crew Diverted; Flight Crew Overcame Equipment Problem
Aircraft
We were on the approach when we lowered the gear handle. The left main gear showed a red light and the other two (right main and nose) were green. This indicated to us that the left main gear was not down and locked. The Captain called for a go-around and we did. We climbed up to a safe altitude and attempted to bring down the gear two more times but continued to only get two green lights. We started to run the checklist needed in the QRH but realized we had to make a decision on where to land because the weather [at our destination] was above and below mins constantly. We made the choice to divert to our alternate because the weather there was above one mile visibility and the longest runway was 12;000 ft. As we got closer to [the alternate]; we continued to run the required QRH checklist and ended up using the Manual Gear Extension Lever to lower the left main gear. After doing this; we had our three green lights needed for us to land safely. Upon landing; the gear held the weight of the aircraft and we taxied to the gate safely.
Having one of our Pilots in the back of our aircraft; we asked him to double check through the gear viewer in the Passenger cabin to confirm the left main wheel down and locked. It was confirmed and we landed uneventfully.
B737 flight crew reported no green light on the Left Main Gear on initial extension. Aircraft diverted due to weather and runway length and landed uneventfully after manual gear extension.