N212351211

General Motors has decided to conduct a voluntary emissions recall involving certain vehicles, equipped with a diesel engine. The Engine Control Module (ECM) may not properly detect faults, set DTCs or illuminate the Malfunction Indicator Light (Check Engine Light) if these fault conditions occur:
•Charge Air Cooler (CAC) low efficiency (DTC P026A)
•Exhaust Gas Recirculation (EGR) cooler low efficiency (DTC P2457)
•NOx sensor position 1 slow response (DTC P22F9) Dealers are to reprogram the Engine Control Module (ECM) with corrected software.