As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRFOIL ICE PROTECTION PRESSURE ABNORMAL LIGHT ILLUMINATED AFTER TAKEOFF. WING ANTI-ICE BLUE LIGHT WAS NOT ON. FLIGHT RETURNED TO DTW AND LANDED WITHOUT INCIDENT. MAINTENANCE CONFIRMED POWER TO WING VALVE AT PIN-B IN LEFT WHEEL WELL. REPLACED LEFT WING ICE PROTECTION SHUTOFF VALVE, OPERATIONAL CHECK NORMAL.