As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA - WHILE ON APPROACH TO LAND, THE MAIN GEAR BEGAN TO CYCLE WITH THE GEAR HANDLE IN THE UP POSITION. LEFT AND RIGHT GEAR UNSAFE AND L DOOR ILLUMINATED FOR ABOUT 5 SEC BEFORE RETURNING TO ALL DARK (NORMAL) INDICATION. LOWERED GEAR NORMALLY, ALL INDICATIONS AND LANDING NORMAL. FERRIED TO PDX FOR REPAIRS. RIGGED LT MLG DOOR CLOSED PROX SENSOR, AMM TASK 32-61-06-830-801, REPLACED L/G CONTROL PANEL AMM TASK 32-31-01-400-801, CHECKS GOOD. RETURNED TO SERVICE.