As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHEN AIRCRAFT IS FLOWN THROUGH RAIN THE TRANSMISSON OIL, RED WARNING LIGHT COMES ON. THE LIGHT GOES OUT SHORTLY AFTER AIRCRAFT IS NOT IN RAIN. THE PRESSURE AND TEMPERATURE ARE IN THE NORMAL RANGE WHEN THE LIGHT COMES ON. CLEANED TRANSMISSION OIL PRESSURE SWITCH TERMINAL FREE OF ALL WATER. FUNCTION TEST GOOD.