As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) THE CREW REPORTED THAT DURING FLIGHT THE LEFT ENGINE FIRE WARNING CAME ON INTERMITTENTLY. THE LIGHT INDICATION OCCURS ONLY AFTER PRECIPITATION OR AIRCRAFT WASHING. FOUND FIRE DETECTOR TRIGGER VOLTAGE LEAKING THROUGH WIRE INSULATION WHEN IT IS WET.