Cummins Fault Code
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Active Regen Inhibited
System
Emissions
Symptom
Active Regen Inhibited
Diagnosis & fix steps
LOGIC: Outlet NOx Sensor Voltage Below Normal.
ACTION: Inspect the sensor harness for a short to ground. Measure voltage at the 4-pin connector.
Red Seal field insights
Logic: A shorted sensor "freezes" the emissions logic, preventing the machine from cleaning the DPF.
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