As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FUMES IN FLIGHT PRESENT OXYGEN MASKS WERE USED AT 100 PERCENT EMERGENCY WAS DECLARED AT CRUISE, FL380. DIVERT TO LIGHT PERFORMED GVI OF AVIONICS BAY EQUIPMENT RACKS & WIRING. ACFT FOUND NORMAL T/S ITEM 3 ON L/P 824502 FOUND ACU-2 FAILED SUSPECT ACU-2 CAUSE OF FUMES R & R ACU IAW 33-15-01-000 AND 400 TEST NORMAL.