What was found
ON GROUND WHEN PACKS ARE WORKING EITHER WITH APU BLEED OR ENGINES BLEED, A HYD LIKE ODOR IS PERCEIVED FROM THE AIR CONDITIONING SYS IAW AMM: TASK 21-00-00- 615-804 PART B THE BLEED AIR DUCTS FROM APU WAS CHECKED FOR CONTAMINATION. NO EVIDENCE WAS FOUND, THE APU AND PACKS WERE OPERATED AND NO ODOR IS PRESENT.