What was found
RECEIVED A LEVEL 3 ALERT CABIN SMOKE AFTER LANDING & DURING TAXI IN. CHECKED AIR SYNOPTIC & NOTICED 7 SMOKE DETECTORS ACTIVE. RAN EVAC CHECKLIST & BLEW CREW ENTRANCE DOOR 1L & SLIDE, EVACUATED ACFT. SHGN WITH GND POWER ON ACFT ALL UPPER CARGO DECK SMOKE DETECTORS WERE ILLUMINATED ON DU 4 & CABIN SMOKE ON OVERHEAD AIR PANEL WAS ILLUMINATED & CABIN SMOKE LEVEL 3 ALERT ON DU 3. THEN ALL INDICATION WENT NORMAL. CHECKED MSG NO CURRENT FAULTS. CHECKED FAULTS LAST LEG SHOWED 4 FAULTS, 1. CFDIU 2. DEU-1 3. DEU-2 & 4. DEU-3. PERFORMED RTS TEST ON MSC AIR DATA HEATERS, TEST PASSED. PERFORMED CARGO SMOKE TEST IAW MM 26-15-00-0, CHECKED NORMAL, NO FAULTS AT THIS TIME.