As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX FLIGHT NR 2359 AFTER TAKE OFF AND RETRACTING LANDING GEAR, LT AMBER DOOR LIGHT AND RED GEAR LIGHT CYCLED, AND GEAR HANDLE LIGHT CYCLED. REPLACED LT HAND GEAR DOOR PROXIMITY SENSOR. OPERATIONAL CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.