As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DTW - FLT 621 - RIGHT MAIN GEAR RED LIGHT ON RETRACTION. AFTER EXTENDING GEAR, GREEN LIGHT FLASHING ON AND OFF WHILE RED FLASHED OFF AND ON. REMOVED AND REPLACED RIGHT MAIN LANDING GEAR DOWNLOCK WARNING PROXIMITY SENSOR IAW MM 32-60-1. JACKED AND PERFORMED GEAR SWING. OPS CHECK GOOD. NO DEFECTS NOTED. (M)