As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: IN DESCENT WITH POWER AT IDLE SLIGHT MUSTY SMELL FROM PACKS. MAINTENANCE FOUND A RESIDUAL HYDRAULIC FLUID STREAK FRM THE RIGHT-HAND MAIN LANDING GEAR WHEEL WELL TO THE APU INLET. A LEAK CHECK OF THE HYDRAULIC SYSTEM RESULTED IN NO LEAKS BEING NOTED. MAINTENANCE ACCOMPLISHED A DECONTAMINATION OF THE ENVIRONMENTAL CONTROL SYSTEM PER TASK CARD 26L00021013 WITH NO REMAINING ODORS NOTED.