As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTS THAT UPON APPROACH AT 30 FT THE RT WING DROPPED SEVERELY. UPON POST FLIGHT ENTIRE RT WING EXCEPT THE LAST 7 FEET WAS COVERED IN A 1/4 TO HALF INCH OF ICE. ALL INDICATIONS WERE GREEN ON APPROACH. MAINTENANCE REMOVED AND REPLACED THE CONTROL SENSOR, THE ANTI-ICE CONTROLLER, AND THE ANTI-ICE SOV IAW THE AMM. THE SYSTEM HAS BEEN INDICATING PROPERLY SINCE. REPLACED PIN HH ON CONNECTOR P226.