As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: AN EMERGENCY WAS NOT DECLARED DUE TO: DURING DESCENT WITH ENGINE ANTI-ICE ON, THE LEFT ENGINE SHOWED AN AMBER TAI LIGHT, WITH A BRIGHT BLUE COWL VALVE OPEN LIGHT. AIRCRAFT DIVERTED TO AND LANDED SAFELY AT IND. REMOVED AND REPLACED NUMBER 1 ENGINE ANTI-ICE VALVE. PER AMM 30-21-11.