As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
L PITOT HEAT CAUTION DURING CLIMB OUT IN ICING CONDITIONS. RAN QRH, PROBLEM DID NOT RESOLVE. (FLIGHT 3589) REMOVED AND REPLACED L PITOT HEAT ADS HEAT CONTROLLER PER CRJ 900 AMM 30-31-15. OPERATIONAL TEST GOOD. PERFORMED OPERATIONAL TEST OF ICE DETECTOR SENSOR FOR L PITOT HEAD PER CRJ 900 AMM 30-31-00. OPERATIONAL TEST GOOD. COULDN€™T DUPLICATE FAULT