Narrative:

On descent into ZZZ; the wing anti-ice and anti-ice inoperative EICAS messages were presented. Followed the QRH and exited icing conditions. Contacted dispatch and maintenance control. Ran troubleshooting checklist with maintenance. The message cleared. Performed the second part of the 2-PART ice test and it passed. Checked for conditions in the surrounding areas. Ice was reported throughout the area of endurance of the aircraft. Decided with maintenance and dispatch to continue to ZZZ. On second descent into ZZZ; the message appeared again. Burning well into the reserve fuel; and being high minimums (WX in the previous hour 1-2 mi); decided to declare an emergency and landed in ZZZ per the QRH.

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Original NASA ASRS Text

Title: EMB145 FLT CREW EXPERIENCES WING ANTI-ICE FAILURE DURING DESCENT; AND AFTER TROUBLESHOOTING; DESCENDS THROUGH ICING CONDITIONS TO LAND AT DESTINATION.

Narrative: ON DSCNT INTO ZZZ; THE WING ANTI-ICE AND ANTI-ICE INOP EICAS MESSAGES WERE PRESENTED. FOLLOWED THE QRH AND EXITED ICING CONDITIONS. CONTACTED DISPATCH AND MAINT CTL. RAN TROUBLESHOOTING CHKLIST WITH MAINT. THE MESSAGE CLRED. PERFORMED THE SECOND PART OF THE 2-PART ICE TEST AND IT PASSED. CHKED FOR CONDITIONS IN THE SURROUNDING AREAS. ICE WAS RPTED THROUGHOUT THE AREA OF ENDURANCE OF THE ACFT. DECIDED WITH MAINT AND DISPATCH TO CONTINUE TO ZZZ. ON SECOND DSCNT INTO ZZZ; THE MESSAGE APPEARED AGAIN. BURNING WELL INTO THE RESERVE FUEL; AND BEING HIGH MINIMUMS (WX IN THE PREVIOUS HR 1-2 MI); DECIDED TO DECLARE AN EMER AND LANDED IN ZZZ PER THE QRH.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.