As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SFO - LT MLG RED INTRANSIT LIGHT REMAINED ILLUMINATED FOLLOWING GEAR RETRACTION. AIRCRAFT RETURNED TO STATION WITHOUT INCIDENT. MAINTENANCE CLEANED AND ADJUSTED LT MLG UPLOCK PROXIMITY SENSOR. LANDING GEAR OPERATION AND POSITION INDICATIONS NORMAL ON GROUND AND DURING SUBSEQUENT TEST FLIGHT. AIRCRAFT RETURNED TO SERVICE. (X)