48 Cummins Fault Codes · 6 System Categories
Cummins ECM Fault Code Lookup
Find what a Cummins fault code means, what commonly causes it, and what a technician should check first — organized by engine system.
Aftertreatment22 codes
Cummins Aftertreatment
DPF, DEF, SCR, and NOx-reduction system faults.
EGR6 codes
Cummins EGR
Exhaust gas recirculation valve, cooler, and flow faults.
Turbo4 codes
Cummins Turbo
Turbocharger boost control and air-handling faults.
Derate3 codes
Cummins Derate
Engine protection and emissions inducement power-limiting faults.
Fuel8 codes
Cummins Fuel
Fuel delivery, injector, and rail pressure faults.
VGT5 codes
Cummins VGT
Variable geometry turbocharger actuator and calibration faults.
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