As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD - FLT 1226 - RED LEFT MAIN GEAR INDICATOR LIGHT FLICKERED OCCASIONALLY IN CLIMB-OUT FROM FL200 TO FL280 THEN REMAINED OUT. FOUND LEFT MAIN UPLATCH PROXIMITY SENSOR BAD. REMOVED AND REPLACED LEFT MAIN UP LATCH PROX SENSOR. SYSTEM OPS CHECKS GOOD. PERFORMED PROX BOX TEST. OPS CHECK GOOD. (M)