What was found
ON SHORT FINAL 600 AGL, F/A REPORT SMOKE IN CABIN. PERFORMED POM AND SMOKE CLEARED. SMOKE SMELLED LIKE BLEED AIR. SMOKE CLEARED AFTER A/C PACKS TURNED OFF. BOTH PACK OIL LEVEL CHECK OK. COALESCER BAGS, NO CONTAMINATION AND CLEAN. ENG BLEED DUCT CHECKED, NO CONTAMINATION. BOTH PACKS OPS WITH APU, NO FAULTS. DUCT BURN-OUT PROCEDURE C/W PACK OPERATING WITH ENG RUNNING NORMAL.