As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOS - FLT 4316 - CREW REPORTED THAT WHEN THE LEFT CABIN AIR RECIRCULATION FAN WAS SELECTED OFF, THE RT CABIN RECIRCULATION FAN INDICATOR LIGHT WOULD ILLUMINATE AND VICE VERSA. MAINTENANCE FOUND LT AND RT CABIN RECIRCULATION FAN SPEED SENSOR WIRING HARNESSES REVERSED AT AIRFRAME RECEPTICALS. CONNECTORS WERE CORRECTLY INSTALLED AND SYSTEM TESTED GOOD. (X)