What was found
BURING WIRE ODOR WAS PRESENT DURING DESCENT. SUPP A/C ON, BOTH BLEEDS WERE ON, NO CAUTION OR WARNING INDICATIONS PRESENT. ODOR WAS STRONGEST IN COCKPIT AND DISSIPATED AFT OF F/A JUMPSEAT. MAINTENANCE DETERMINED ODOR TO BE DUE TO RT ACM BEING CEASED. REMOVED AND REPLACED ACM P/N 776910-6, S/N OFF 880342, S/N ON 8614121, IAW JOB CARD 215181, OPS CHECK GOOD.