42 Mack Fault Codes
Mack ECM Fault Codes
Mack diesel ECM fault codes across aftertreatment, EGR, turbo, and derate systems.
Aftertreatment12 codes
Mack Aftertreatment
DPF, DEF, SCR, and NOx-reduction system faults.
EGR11 codes
Mack EGR
Exhaust gas recirculation valve, cooler, and flow faults.
Turbo9 codes
Mack Turbo
Turbocharger boost control and air-handling faults.
Derate10 codes
Mack Derate
Engine protection and emissions inducement power-limiting faults.
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