As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURN BACK DUE TO WING A/I FAIL AND EXPECTING ICE CONDITIONS REROUTE. PERFORMED ICE TEST AIRBORNE ALL OK EXCEPT WING A/ICE FAIL. PERFORMED OPS CHECK WING A/ICE SYSTEM IAW EMB 145 AMM 30-10-00. COULD NOT DUPLICATE THIS PROBLEM AT THIS TIME. NO PARTS CHANGED, AIRCRAFT RETURNED TO SERVICE.