What was found
INFLIGHT WITH WING ANTIICE ON IN NORMAL MODE, RECEIVED WING OVERHEAT WARNING. SUSPECT LEFT WING. C/W'D QRH & SELECTED WING ANTI-ICE OFF. MESSAGE CLEARED IMMEDIATELY. PER QRH, SELECTED WING ANTI-ICE TO STBY, THEN RECEIVED LEFT WING ANTI-ICE CAUTION & SYNOPTIC SHOWED LEFT WING AMBER. C/W'D QRH & SELECTED 14TH ISOL OPEN, LEFT WING ANTI-ICE CAUTION CLEARED & THEN REOCCURRED. CLEARED ICING CONDITIONS & SELECTED WING ANTIICE OFF. UPON RE-ENTERING ICING CONDITIONS, SELECTED ANTIICE ON IN STBY WITH 14TH ISOL VALVE OPEN , NO ANTIICE MESSAGES PRESENT. DIVERTED.