As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SFO - LANDING GEAR FAILED TO RETRACT AFTER TAKEOFF. AIRCRAFT RETURNED TO STATION WITHOUT INCIDENT. REPLACED LANDING GEAR CONTROL MODULE AND RELAY BOX. LANDING RETRACTION AND EXTENSION NORMAL DURING GROUND TEST AND SUBSEQUENT TEST FLIGHT. AIRCRAFT RETURNED TO SERVICE. (W)