What was found
DURING DESCENT, ENGINE IDLE HAD STRONG DIRTY SOCK ODOR IN THE FLIGHT DECK ONLY. THE AIRCRAFT WAS GROUNDED. COMPLIED WITH JC 26L00021001, 26L00021002, 26L00021004, AND 26L00021005. R & R BOTH PACKS OZONE FILTERS, CONDENSORS, REHEATERS, AND WATER EXTRACTORS IAW MULTIPLE NON-ROUTINES. REPLACED THE APU IAW JC 26L31049003. OPS AND LEAK CHECKED GOOD.