As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
LT AIR VALVE LIGHT CAME ON AFTER TAKEOFF. CYCLED ANTI-ICE ON AND AIR VALVE LIGHT ON LT SIDE ILLUMINATED. AIR TURNBACK TO DTW. MAINTENANCE REPLACED LT GARRET VALVE P/N 5056T88P01, S/N OFF AEX10253, S/N ON AEX10424, IAW CT7-MM. OPS CHECK GOOD.