CB22-J-003

Isuzu Motors Limited has determined that certain 2015 model year Isuzu N-Series trucks equipped with 5.2L (4HK1) diesel engines were built with an Engine Control Module (EC) containing an On-Board Diagnostic (OBD) calibration error for Diagnostic Trouble Code (DTC) P0401 Exhaust Gas Recirculation (EGR) Flow Insufficient. As a result, the ECM was not sensitive enough to detect DTC P0401 at the appropriate time, which would normally cause the check engine Malfunction Indicator Light (MIL) to illuminate. Isuzu has corrected the calibration so DTC P0401 can be detected properly.