As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR DISTRIBUTION: WHILE CRUISING AT FL 400 WE SMELLED SMOKE/ FUMES IN THE COCKPIT. WE COULD NOT LOCATE THE SOURCE OF IT. THE SMELL/ FUME GOT STRONGER AS TIME PROGRESSED. CORRECTIVE ACTION: REMOVED FAULTY FWD EVAPORATOR BLOWER AND REPLACED WITH A NEW BLOWER. PERFORMED SATISFACTORY OPS CHECKS REF PHENOM 300 AMM 21-52-04. REMOVED P/N 1133850-104 S/N 1076