As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LEFT INTAKE CYCLES ON/OFF. AIR RETURN TO DTW. MAINTENANCE PERFORMED FAULT ISOLATION PROCEDURES IAW SF340 MM 30-20-00. ALL CHECKS GOOD. DID FIND ONE CONNECTOR LOOSE ON CONTROLLER TIGHTEN AS REQUIRED. GROUND RAN FOR 30 MINUTES, ALL CHECKS GOOD.