As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX FLIGHT NR 2308: NR 1 BLEED HOT CAUTION LIGHT DURING DESCENT. TURNED OFF BLEED PER CHECKLIST. LIGHT EXTINGUISHED. ALSO DUCT TEMPS ALL NORMAL. MAINTENANCE INTERROGATED CDS. FOUND LEFT ANA WING LOOP FAULT. REPLACED NR 1 NACELLE DUCT LEAK OVER TEMP SWITCH IAW Q400 AMM 36-11-21-000-801 AND 36-21-11-400-801. GROUND RAN ENGINE. OPS CHECK GOOD. AIRCRAFT RETURNED TO SERVICE.