Group 28 Engine Control Module (ECM) Diagnostic Trouble Codes (DTCs) ECM SPN 3936, Aftertreatment DPF System – MID 128 PSID 28 ECM SPN 4094, NOx Limits Exceeded Due to Insufficient Diesel Exhaust Fluid (DEF) Quality MID 128 PSID 90 ECM SPN 4095, NOx Limits Exceeded Due to Interrupted Diesel Exhaust Fluid (DEF) Dosing MID 128 PSID 90 77 Type of fault: FMI Description: Fault Condition: Possible Symptoms: Possible Cause:
FMI 0 • Data valid but above normal operational range - Most severe level • Aftertreatment DPF differential pressure sensor value too high • MIL illuminated • Aftertreatment DPF differential pressure sensor • Aftertreatment particulate filter FMI 1 • Data valid but below normal operational range - Most severe level • Aftertreatment DPF differential pressure sensor value too low • MIL illuminated • Aftertreatment DPF differential pressure sensor • Aftertreatment particulate filter Type of fault: FMI Description: Fault Condition: Possible Symptoms: Possible Cause:
FMI 1 • Data valid but below normal operational range - Most severe level • Aftertreatment Diesel Exhaust Fluid (DEF) dosing too low • Yellow electronic malfunction lamp illuminated • Engine derate • DEF quality • Aftertreatment DEF line clogged • Aftertreatment doser • Aftertreatment control module failure FMI 14 • Special Instructions • Aftertreatment Diesel Exhaust Fluid (DEF) dosing too low • Yellow electronic malfunction lamp illuminated • Engine derate • DEF quality • Aftertreatment DEF line clogged • Aftertreatment DEF dosing • Aftertreatment control module failure FMI 18 • Data valid but below normal operating range - Moderately severe level • Aftertreatment Diesel Exhaust Fluid (DEF) dosing too low • Yellow electronic malfunction lamp illuminated • Engine derate • DEF quality • Aftertreatment DEF line clogged • Aftertreatment DEF dosing • Aftertreatment control module failure Type of fault:
FMI Description: Fault Condition: Possible Symptoms: Possible Cause: FMI 7 • Mechanical system not responding or out of adjustment • Dosing failure • MIL illuminated • Aftertreatment Diesel Exhaust Fluid (DEF) low usage • DEF level • Faulty DEF pump • Leak in DEF hose