Cummins Standby Generators Error Codes

Fault Code 111

Generator will not start; controller shows Fault Code 111 – Overcrank

Overcrank / Failure to Start

Fault Code 115

Generator shuts down shortly after start; controller shows Fault Code 115 – Low Fuel Pressure

Low Fuel Pressure Shutdown

Fault Code 1150

Controller displays Fault Code 1150 – Fuel Level Low (if tank sender connected); generator may not start or may shut down

Low Fuel Level Detection

Fault Code 143

Generator shuts down; controller displays Fault Code 143 – Low Oil Pressure

Low Oil Pressure Shutdown

Fault Code 1431

Controller displays Fault Code 1431 – Oil Pressure Sensor Circuit Fault

Oil Pressure Sensor Electrical Fault

Fault Code 1435

Generator shuts down; controller displays Fault Code 1435 – Low Oil Level (if equipped with level sensor)

Low Engine Oil Level Detection

Fault Code 1436

Controller shows Fault Code 1436 – Oil Temperature High (if equipped); generator shuts down

High Oil Temperature Shutdown

Fault Code 151

Generator shuts down; controller shows Fault Code 151 – High Engine Temperature

Engine Overtemperature Shutdown

Fault Code 1511

Controller shows Fault Code 1511 – Coolant Temperature Sensor Circuit Fault

Coolant Temperature Sensor Electrical Fault

Fault Code 156

Generator shuts down; controller displays Fault Code 156 – Low Coolant Level

Low Coolant Level Shutdown

Fault Code 1682

Controller displays Fault Code 1682 – Low Battery Voltage; generator may fail to start or controller resets intermittently

Low DC Supply Voltage

Fault Code 1683

Controller displays Fault Code 1683 – High Battery Voltage; possible DC alarms and controller protection shutdown

High DC Supply Voltage

Fault Code 1688

Controller displays Fault Code 1688 – ECM Internal Failure

Engine Control Module Internal Error

Fault Code 235

Controller shows Fault Code 235 – ECM Power Supply Voltage Low; intermittent shutdowns or no start

Engine Control Module Low Voltage

Fault Code 2359

Generator derates or shuts down; controller shows Fault Code 2359 – Air Intake System Restriction

Air Intake Restriction / High Intake Manifold Pressure Differential

Fault Code 2371

Generator derates or logs Fault Code 2371 – Fuel Rail Pressure Too Low (common rail diesel models)

Low High-Pressure Fuel Rail Pressure

Fault Code 2372

Controller logs Fault Code 2372 – Fuel Rail Pressure Too High (common rail diesel)

High Fuel Rail Pressure

Fault Code 2375

Generator derates; controller shows Fault Code 2375 – Turbocharger Boost Pressure Low

Low Turbo Boost / Air System Performance

Fault Code 415

Generator shuts down; controller shows Fault Code 415 – Overspeed

Engine Overspeed Shutdown

Fault Code 4150

Controller displays Fault Code 4150 – Loss of Engine Speed Signal; generator shuts down

Engine Speed Signal Loss

Fault Code 4152

Generator shuts down; controller shows Fault Code 4152 – Underfrequency

Underfrequency / Underspeed Protection

Fault Code 4153

Generator shuts down; controller shows Fault Code 4153 – Overfrequency

Overfrequency / Overspeed Protection (mild)

Fault Code 4155

Controller shows Fault Code 4155 – Generator Field Overcurrent / Excitation Fault

Excitation System Overcurrent

Fault Code 419

Generator shuts down; controller displays Fault Code 419 – Overvoltage

Generator Overvoltage Protection Trip

Fault Code 420

Generator shuts down; controller displays Fault Code 420 – Undervoltage

Generator Undervoltage Protection Trip

Fault Code 427

Generator shuts down; controller shows Fault Code 427 – Phase Imbalance / Voltage Unbalance

Three-Phase Voltage Imbalance

Fault Code 441

Generator shuts down; controller displays Fault Code 441 – Overcurrent

Generator Overcurrent / Overload Trip

Symptom

Battery repeatedly goes dead between exercise runs

Chronic Battery Discharge

Symptom

Controller display is blank or intermittent, generator otherwise appears intact

Control Panel Power Loss

Symptom

Corrosion and rust forming inside generator enclosure

Moisture Ingress / Corrosion

Symptom

Exhaust smoke is excessive (black, blue, or white) during operation

Abnormal Exhaust Smoke

Symptom

Fuel odor around Cummins standby generator enclosure

External Fuel Leak

Symptom

Generator cranks but does not start (no firing)

No Start – Fuel or Ignition Failure

Symptom

Generator enclosure is overheating inside, even if engine temperature is normal

Poor Enclosure Ventilation

Symptom

Generator fails to exercise automatically on schedule

Auto-Exercise / Auto-Start Scheduling Failure

Symptom

Generator is excessively noisy or has unusual knocking sounds

Abnormal Engine Noise

Symptom

Generator produces correct voltage but frequency is low or high (e.g., not 60 Hz)

Incorrect Engine Speed / Frequency

Symptom

Generator runs but does not transfer power to the building

Automatic Transfer Switch / Output Contactor Failure

Symptom

Generator runs but output voltage is unstable or fluctuates

Unstable Voltage Regulation

Symptom

Generator shuts down when large motor loads start (e.g., well pump, AC compressor)

Load Step / Motor Starting Issue

Symptom

Generator starts then stops after a few seconds with no specific code

Run-Then-Stop – Safety Interlock or Sensor Issue

Symptom

Generator vibrates excessively during operation

Excessive Vibration

Symptom

Visible coolant leak or puddle under generator

External Coolant Leak