What was found
(CAN) APPROXIMATELY .5 MILE BACK ON APPROACH, HAD A RED CAUTION ON THE ENGINE PAGE FOR LOW PRESSURE SHOWING 6 PSI AND HAD TO BRING ENGINE BACK TO IDLE. NO ECAM MESSAGE WAS DISPLAYED FOR THE CONDITION. ON TAXI-IN, AS A PRECAUTIONARY MEASURE, ENGINE WAS SHUTDOWN AND SINGLE ENGINE TAXI IN. MAINTENANCE IS INVESTIGATING. LUBRICATION UNIT MAGNETIC PLUGS INSPECTED IAW AMM 79-21-10-210-002. NO EXTERNAL OIL LEAKS NOTED, FLAME ARRESTOR NOT CLOGGED, NO DISCHARGE FROM CENTER VENT TUBE. ENGINE DRY CRANKED TO MAX MOTOR WITH 12 PSI INDICATED. DISCUSSION WITH MOC, OIL PRESSURE TRANSMITTER REPLACED IAW AMM 79-33-15 PB 401.