As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ETOPS SIGNIFICANT SYSTEM -ON DESCENT WITH BOTH THROTTLES IN IDLE, GET L ENG ANTI-ICE EICAS AND VALVE ANNUNCIATOR LIGHT WHEN TRYING TO ENGAGE ANTI-ICE. WHEN LEFT THROTTLE WAS PUSHED FORWARD ALL LIGHTS EXTINGUISHED. REPLACED LEFT ENGINE ANTI-ICE VALVE PER AMM 30-21-03/401 AND OPERATIONAL TEST NORMAL.