Cummins Fault Code
Free · no signupCummins 117 (SPN 156 FMI 4)
Engine stalling; Hard start; Severe power derate; Possible white smoke.
System
Not specified
Symptom
Engine stalling; Hard start; Severe power derate; Possible white smoke.
Diagnosis & fix steps
Rail Pressure Voltage Low.
LOGIC: Signal < 0.5V (Short to Ground).
ACTION: Unplug sensor; if code becomes 118, sensor is dead. Check 5V ref on Pin A.
FIX: Replace Rail Pressure Sensor or repair harness short.
Red Seal field insights
Safety Warning: The fuel rail can hold over 20,000 PSI even with the engine off. Never crack a fuel line while this code is active until you've verified actual pressure is low.
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