Cummins/Onan C80 N6 troubleshooting: 80 fault codes and 65 symptom-cause-remedy entries from the manufacturer's own service documentation.
Cummins/Onan C80 N6 — full specs, parts & maintenance.
All Cummins/Onan fault codes →
| Code | Meaning | Cause | Remedy |
|---|---|---|---|
| 135 | Oil Pressure Sensor OOR - High — Engine oil pressure sensor signal is out of range – shorted high | Faulty oil pressure sensor and/or circuit; Faulty ECM; Faulty ECM connection or harness | |
| 144 | Engine Coolant Temperature OOR Low (Warning) — Engine coolant temperature signal voltage is out of range - shorted low | For the troubleshooting procedure, refer to DTC 118 in the E-Controls Service Manual | |
| 145 | Engine Coolant Temperature OOR High (Warning) — Engine coolant temperature signal voltage is out of range - shorted high | For the troubleshooting procedure, refer to DTC 117 in the E-Controls Manual | |
| 146 | Engine Coolant Temperature Above Normal (Warning) — Engine coolant temperature has exceeded the warning threshold (220 °F [105 °C]) for high coolant temperature | High ambient temperature | Measure the air temperature entering the air intake louver of the generator set enclosure if enclosed, or cooling air to the radiator if not enclosed; verify the expected cooling system ambient temperature capability; inspect for recirculation of cooling discharge air into the generator set enclosure air inlet or the area surrounding the radiator cooling air inlet |
| 146 | Engine Coolant Temperature Above Normal (Warning) — Engine coolant temperature has exceeded the warning threshold (220 °F [105 °C]) for high coolant temperature | Coolant level below specification | Inspect the engine, cooling system, and surrounding area for external coolant leaks; repair as required; verify the coolant level is correct; add coolant as necessary |
| 146 | Engine Coolant Temperature Above Normal (Warning) — Engine coolant temperature has exceeded the warning threshold (220 °F [105 °C]) for high coolant temperature | Damaged or obstructed cooling system components | Inspect the radiator, charge air cooler (if used), and other cores (if used) for damaged fins, dirt, debris or obstructions; remove the blockage; inspect the fan shroud for damage and clearance, repair or replace the shroud if damaged; inspect the fan belt(s) for damage, wear, and proper tension and the pulleys and belt tensioner for damage or wear, repair or replace the parts that are damaged or worn; inspect the radiator cap and gasket for damage and proper pressure operation, replace the radiator cap if it is not operating correctly; inspect the upper and lower radiator hoses for collapse, distortion, or fluid leaks, replace the hose(s) if damaged or worn; inspect the cooling system components for internal contaminates (dirt, scale, or sludge) and clean as required; open the radiator cap and inspect for contaminated coolant and scale; flush the cooling system per the engine service manual |
| 146 | Engine Coolant Temperature Above Normal (Warning) — Engine coolant temperature has exceeded the warning threshold (220 °F [105 °C]) for high coolant temperature | Inaccurate coolant temperature sensor | Measure the coolant temperature near the sender and compare it to the coolant temperature displayed on the control panel; verify the temperature sender resistance and compare it to the specification; disconnect the main harness connector from the coolant temperature sensor; measure the resistance between the coolant temperature signal pin and the coolant temperature sensor return pin; if the temperature differs from the unit display by more than 8 °F (13 °C), replace the sensor; verify the continuity of temperature sender leads (harness lead resistance should be less than 0.5 Ohm for each lead from the connection to the PCC control board connector); repair or replace faulty components or wiring |
| 146 | Engine Coolant Temperature Above Normal (Warning) — Engine coolant temperature has exceeded the warning threshold (220 °F [105 °C]) for high coolant temperature | Fault simulation feature enabled | Connect InPower; verify that the fault simulation is disabled for the engine coolant temperature sensor by connecting to the PCC via InPower |
| 146 | Engine Coolant Temperature Above Normal (Warning) — Engine coolant temperature has exceeded the warning threshold (220 °F [105 °C]) for high coolant temperature | Faulty thermostat | Refer to the Coolant Thermostat Troubleshooting section |
| 146 | Engine Coolant Temperature Above Normal (Warning) — Engine coolant temperature has exceeded the warning threshold (220 °F [105 °C]) for high coolant temperature | Malfunctioning water pump | Replace the water pump; refer to the Water Pump Removal and Installation section |
| 146 | Engine Coolant Temperature Above Normal (Warning) — Engine coolant temperature has exceeded the warning threshold (220 °F [105 °C]) for high coolant temperature | Air or combustion gases entering the cooling system | Refer to the engine service manual |
| 151 | Engine Coolant Temperature High (Shutdown) — The engine coolant temperature has exceeded the alarm (shutdown) threshold for high coolant temperature | For the troubleshooting procedure, refer to DTC 217 in the E-Controls Manual | |
| 153 | Intake Manifold Temperature OOR High (Warning) — Engine intake manifold temperature sensor signal is out of range – shorted high | For the troubleshooting procedure, refer to DTC 113 in the E-Controls Manual | |
| 154 | Intake Manifold Temperature OOR Low (Warning) — Engine intake manifold temperature sensor signal is out of range – shorted low | For the troubleshooting procedure, refer to DTC 112 in the E-Controls Manual | |
| 155 | Intake Manifold Temperature High (Shutdown) — The engine intake manifold temperature has exceeded 95 °C (203 °F) for greater than 10 seconds | For the troubleshooting procedure, refer to DTC 127 in the E-Controls Manual | |
| 234 | Engine Speed High (Shutdown) — Engine speed signals indicate an engine speed greater than the shutdown threshold | Faulty Hall Effect (HE) sensor connections and wiring; Faulty HE sensor; Fault simulation feature is enabled; Incorrect threshold setting; Incorrect settings on the E-controls | |
| 286 | CAN Address Conflict Failure (Warning) — There are two or more devices on the network use the same source address | For the troubleshooting procedure, refer to DTC 1628 in the E-Controls Manual; if another Cummins device is found to have the same slave address, refer to that service manual for that device to change the slave address | |
| 359 | Fail to Start — The engine failed to start after the expiration of crank time | Fuel system issues | Inspect fuel lines and fuel connections for leaks; repair if leaks are found; the manual fuel shutoff (FSO) valve is closed - open the valve; the FSO valve solenoids or circuit are malfunctioning - check the FSO valve solenoids and circuit, correct or replace as necessary |
| 359 | Fail to Start — The engine failed to start after the expiration of crank time | Incorrect starter disconnect speed | Connect to the control via the InPower service tool; make sure Starter Disconnect Speed is set to 450 RPM |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Lubricating oil level is low | Check the oil level; add or drain oil, if necessary |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | External leak | Inspect the engine and surrounding area for external oil leaks; tighten the capscrews, pipe plugs, and fittings; replace gaskets that show signs of oil leaks |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Fault simulation is enabled or the threshold is set too high | Connect to the control with InPower and ensure that the fault simulation for LOP is not enabled; using the electronic service tool, verify that the fault threshold is not within the normal operating range for the oil pressure sensor |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Coolant temperature is above specification | |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Lubricating oil does not meet specifications | |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Lubricating oil is contaminated with coolant or fuel | |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Oil pressure sensor is inaccurate or blocked | Connect a properly calibrated mechanical oil pressure gauge to the engine at the plug on top of the oil filter head; connect InPower; while engine is stopped, compare the oil pressure reading on the service tool to the reading on the mechanical oil pressure gauge; only proceed if engine troubleshooting has been completed (do not attempt to start the engine if there is doubt about oil pressure); start the generator set; compare the oil pressure reading on the service tool to the reading on the mechanical oil pressure gauge |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Engine angularity during operation exceeds specification | |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Incorrect lubricating oil cooler is installed | |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Lubricating oil pump is faulty | |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Main oil pressure regulator is faulty | |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Lubricating oil suction or transfer tube is loose or broken | |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Piston cooling nozzles are damaged or are not installed correctly | Inspect capscrew and piston cooling nozzle for damage; check for leaks and improper seating |
| 415 | Engine Oil Pressure Low (Shutdown) — Engine oil pressure is below the low oil pressure shutdown threshold (less than 10 psig for more than 2 seconds) | Lubricating oil filter plumbing is not routed correctly | |
| 1117 | ECM Power Lost — "keyswitch" to the Engine Control Module (ECM) was not removed for 30 seconds before removing battery power to the ECM (removing connectors or battery cable) | ECM power lost | To reset, press the Off button, press the Emergency Stop button, and wait 30 seconds |
| 1244 | Engine Normal Shutdown — The engine has received a normal shutdown request | The generator set is going through a normal shutdown | The generator set is going through a normal shutdown and there are no active shutdown fault(s) in the ECM for at least 2 seconds |
| 1245 | Engine Shutdown Fault — An engine shutdown fault has occurred in the Engine Control Module (ECM), and no other active shutdown faults exist on the PCC | Event/fault code 1245 is activated by another active shutdown fault in the ECM | Connect to the ECM with E-Controls GCP Display or 4G Display to determine the actual shutdown fault that is generating event/fault code 1245; troubleshoot the shutdown fault(s) |
| 1246 | CAN Unknown Engine Fault — The PCC received an unknown message from the ECM | ECM/engine fault | Refer to the E-Controls service tool |
| 1248 | Engine Warning — An engine warning fault has occurred in the Engine Control Module (ECM), and there are no active warning faults on the PCC | Another active warning fault in the ECM activates event/fault code 1248 | Connect to the ECM with E-Controls GCP Display or 4G Display to determine the actual warning fault that is generating event/fault code 1248; troubleshoot the shutdown fault(s) |
| 1311 | Customer Input #1 (Warning or Shutdown) — The nature of the fault is an optional customer selection | Program the fault function using the InPower service tool: enable/disable input (default: enable); status, warning, or shutdown (default: #1-None, #2-Warning and #3-Warning); active closed or open (default: closed [ground]) | |
| 1312 | Customer Input #2 (Warning or Shutdown) — The nature of the fault is an optional customer selection | Program the fault function using the InPower service tool: enable/disable input (default: enable); status, warning, or shutdown (default: #1-None, #2-Warning and #3-Warning); active closed or open (default: closed [ground]) | |
| 1318 | Low Fuel (Warning or Shutdown) — This fault is used when an optional low fuel level switch is installed | Low fuel pressure | Measure the fuel pressure at the fuel pump inlet |
| 1318 | Low Fuel (Warning or Shutdown) — This fault is used when an optional low fuel level switch is installed | Faulty or inoperable switch | Remove the switch and verify proper switch operation; if either of the following conditions is not demonstrated, the switch is defective: when the float is at the bottom of the switch, the wires must show continuity; when the float is raised, the wires must show an open circuit |
| 1318 | Low Fuel (Warning or Shutdown) — This fault is used when an optional low fuel level switch is installed | No actual fault; external wiring problem | Disconnect the signal lead from TB1 and reset the control; disconnect the signal wire from the fuel level switch, check resistance to GND at the J20-18 harness wire or on the back of the annunciator (if equipped), if there is continuity, repair or replace the harness; if the message goes away, the external wiring has a short circuit - check for any grounding of either input, which activates the fault |
| 1318 | Low Fuel (Warning or Shutdown) — This fault is used when an optional low fuel level switch is installed | Incorrect fault function settings are programmed into the control calibration | Verify that control values match the parameters necessary for fault detection |
| 1417 | Power Down Failure — The PCC has failed to go to sleep | Incorrect calibrations in PowerCommand controls | Using the display or the InPower Service tool, verify the calibration in the PCC; if the calibration in the PCC matches the latest calibration on the InCal website, then the calibration is correct, if it does not, update the calibration to the latest |
| 1417 | Power Down Failure — The PCC has failed to go to sleep | Faulty baseboard | Remove power (B+) from the PCC for 5 to 10 seconds and reconnect B+ to the PCC; if the PCC fails to go to sleep after power is cycled from the PCC and the PCC shows event/fault code 1417 again, replace the baseboard |
| 1433 | Local E-Stop — The state of the Local Emergency Stop (E-Stop) has been changed | The local E-Stop button has been activated | Reset the Local E-Stop: pull the Local E-Stop button out; press the Off button; press the Reset button; select Manual or Auto as required |
| 1433 | Local E-Stop — The state of the Local Emergency Stop (E-Stop) has been changed | Faulty connection or faulty E-Stop switch | Verify that the E-Stop button is working properly (closed contact when pulled out, open contact when pressed); check for an open circuit condition in the connection and/or wiring from the Local E-Stop switch to the PCC; a ground connection to the Local E-Stop control input (J25-2 Input; J25-6 Ground) disables the E-Stop alarm; an open circuit should activate the E-Stop alarm |
| 1434 | Remote E-Stop — The state of the Remote Emergency Stop has been changed | The Remote Emergency Stop button has been activated | Reset the Remote Emergency Stop |
| 1434 | Remote E-Stop — The state of the Remote Emergency Stop has been changed | Jumper not installed in control | |
| 1434 | Remote E-Stop — The state of the Remote Emergency Stop has been changed | Faulty connection or faulty Emergency Stop switch | |
| 1855 | Customer Input 3 — Event/fault code 1855 (customer input 3) becomes active when there is a ground input at TB1-3 on the back of the universal annunciator | Incorrect annunciator configuration or wiring; Faulty sender, relay, or device activating Input 3; Faulty annunciator | Make sure that the universal annunciator is correctly configured; check the wiring at TB1-3 and make sure that customer input 3 is wired correctly, make sure that there is not a short or open circuit at the TB1-3 connection; check the sender, relay, or device that is activating Input 3 on the universal annunciator, replace if faulty; if the wiring and configuration is satisfactory, replace the universal annunciator |
| 1944 | Annunciator Configuration Error (Warning) — More than one network device is configured to activate one of the annunciator output relays | Bad network configuration | Check the setup of devices on the network against duplicate use of the same annunciator relay output |
| 1944 | Annunciator Configuration Error (Warning) — More than one network device is configured to activate one of the annunciator output relays | Bad device on network | Troubleshoot the network for malfunctioning devices |
| 2118 | Fuel Pressure Low — This fault is used when an optional low fuel pressure switch is installed | Low fuel pressure | Check fuel supply and change as required |
| 2118 | Fuel Pressure Low — This fault is used when an optional low fuel pressure switch is installed | Faulty fuel pressure switch connections | Inspect the fuel pressure switch and the harness connectors; disconnect the harness connector from the fuel pressure switch; inspect for corroded pins, bent or broken pins, pushed back or expanded pins; inspect for evidence of moisture in or on the connector; inspect for dirt or debris in or on the connector pins; inspect the wiring for any damage or shorting |
| 2118 | Fuel Pressure Low — This fault is used when an optional low fuel pressure switch is installed | Faulty fuel pressure switch | Check switch operation; turn off the fuel supply to the unit, and vent fuel in the line, check for continuity across the two leads of the switch (the circuit should be open); turn fuel supply to the unit on, and check for continuity across the two leads of the switch (the circuit should be closed) |
| 2118 | Fuel Pressure Low — This fault is used when an optional low fuel pressure switch is installed | Incorrect fuel system selected in control | Verify fuel system selection in control menu; refer to the Converting the Fuel System Type section |
| 2118 | Fuel Pressure Low — This fault is used when an optional low fuel pressure switch is installed | Faulty control board | If the sender, harness and control settings are acceptable, the baseboard is defective; replace it |
| 2335 | Excitation Fault (Loss of AC Sense) — The control has lost voltage sensing or has lost zero cross sensing | Incorrect configuration; Bad fuse; Bad wire harness or wrong connections; Low resistance | |
| 2677 | Fail to Stop (Shutdown) — The generator set continues to run after receiving shutdown command from the controller | Stuck fuel shutoff (FSO) valve | Check keyswitch operation and make sure it is not stuck closed (use a multimeter and check continuity across the relay K3-1 and K3-4; with the Emergency stop pressed, the relay should be open); check for a stuck FSO valve, check the FSO relay and related wiring, check that the FSO is not mechanically stuck; if issue persists, consult DTC 1181 in the E-Controls manual |
| 2729 | IO Module Lost (Warning) — There is an intermittent data link between the I/O module and the PCC control (Aux 101 I/O Module option) and no input fault levels were set to Shutdown | Incorrect wiring | The connection between AUX 101 and PCC 1302 is incorrect; make sure there is proper wiring: PCC 1302 TB1-1 – PCC Net A (+) to AUX 101 J1-3; PCC 1302 TB1-2 – PCC Net B (-) to AUX 101 J1-4; PCC 1302 TB1-3 – B+ Return to AUX 101 J14-2; PCC 1302 TB1-5 – Customer Fused B+ to AUX 101 J14-1; PCC 1302 TB15-5 – System Wake-up to AUX 101 J1-5 |
| 2729 | IO Module Lost (Warning) — There is an intermittent data link between the I/O module and the PCC control (Aux 101 I/O Module option) and no input fault levels were set to Shutdown | I/O settings misconfigured | If no AUX 101 is connected to PCC 1302, connect to the InPower service tool; go to Adjustments > System I/O Adjustment > Output Relays, make sure System IO Board Enable is disabled; go to Adjustments > System I/O Adjustment, make sure no inputs or outputs are configured as enabled |
| 2731 | IO Module Lost (Shutdown) — Indicates an intermittent data link between the I/O module and the PCC control (Aux 101 I/O Module option) and at least one input fault level was set to Shutdown | Incorrect wiring | The connection between AUX 101 and PCC 1302 is incorrect; make sure there is proper wiring: PCC 1302 TB1-1 – PCC Net A (+) to AUX 101 J1-3; PCC 1302 TB1-2 – PCC Net B (-) to AUX 101 J1-4; PCC 1302 TB1-3 – B+ Return to AUX 101 J14-2; PCC 1302 TB1-5 – Customer Fused B+ to AUX 101 J14-1; PCC 1302 TB15-5 – System Wake-up to AUX 101 J1-5 |
| 2731 | IO Module Lost (Shutdown) — Indicates an intermittent data link between the I/O module and the PCC control (Aux 101 I/O Module option) and at least one input fault level was set to Shutdown | I/O settings misconfigured | If no AUX 101 is connected to PCC 1302, connect to InPower; go to Adjustments > System I/O Adjustment > Output Relays, make sure System IO Board Enable is disabled; go to Adjustments > System I/O Adjustment, make sure no inputs or outputs are configured as enabled |
| 2897 | Factory Memory Block Corrupt — The control has detected a corrupted memory block | Defective memory block | Connect to device using InPower version 10.0 or greater; in InPower, right click on the device, and select Initial Calibration (Recover Device) from the menu that appears; if the capture file for the device is available, select "overlay capture file", if not, select feature codes (feature codes can be found on the nameplate of the device, located on the alternator housing); if the problem persists, contact the factory for support |
| 2898 | Periodic or Fault Memory Block Corrupt — The control has detected a corrupted memory block | Defective memory block | Connect to the device using InPower version 10.0 or greater; in InPower, right click on the device, and select Initial Calibration (Recover Device) from the menu that appears; if the capture file for the device is available, select "overlay capture file", if not, select feature codes (feature codes can be found on the nameplate of the device, located on the alternator housing); if the problem persists, contact the factory for support |
| 2899 | User Memory Block Corrupt — The control has detected a corrupted memory block | Defective memory block | Connect to the device using InPower version 10.0 or greater; in InPower, right click on the device, and select Initial Calibration (Recover Device) from the menu that appears; if the capture file for the device is available, select "overlay capture file", if not, select feature codes (feature codes can be found on the nameplate of the device, located on the alternator housing); if the problem persists, contact the factory for support |
| 2911 | Trim Memory Block Corrupt — The control has detected a corrupted memory block | ||
| 2964 | Intake Air Temperature Higher than Expected — The manifold air temperature exceeds 94 °C (200 °F) for more than 60 seconds, while the engine is running (DTC 111 active). | Exhaust air entering intake | Inspect the exhaust system for leaks. Check the exhaust manifold gaskets, turbo gasket (if equipped), and exhaust tubing for holes or escaping exhaust. Replace the faulty component(s) if necessary; The unit is not properly ventilated. Make sure that the unit is greater than 5 feet from any obstruction. For units located inside of a structure, make sure that exhaust gases do not exit within 5 feet of the intake for the structure or generator set. For enclosed sets, make sure that there are no objects blocking the exhaust opening on the top of the enclosure, or objects that may redirect exiting airflow towards the intake end of the unit. |
| 2964 | Intake Air Temperature Higher than Expected — The manifold air temperature exceeds 94 °C (200 °F) for more than 60 seconds, while the engine is running (DTC 111 active). | TMAP sensor failure | Remove TMAP sensor from the intake manifold, and expose it to ambient air; Make sure that the tip is well away from the engine or other heat/cold sources; Connect using the E-controls service tool, and monitor the manifold air temperature. Compare that to the known ambient air temperature; Check for continuity across leads 1 and 2 of the TMAP sensor. If the circuit is open, replace the TMAP sensor. |
| 2972 | Field Overload (Shutdown) — If the time that the Field AVR Duty Cycle is operating at maximum output is longer than the time in the "Max Field Time" parameter, event/fault code 2972 will become active. | Voltage sensing into the baseboard is too low, or there is an open/short circuit | |
| 2972 | Field Overload (Shutdown) — If the time that the Field AVR Duty Cycle is operating at maximum output is longer than the time in the "Max Field Time" parameter, event/fault code 2972 will become active. | Applicati | |
| Code 141 | - Oil pressure sensor output out of range low | ||
| Code 143 | - Engine oil pressure low (warning) | ||
| Code 144 | - Engine coolant temperature out of range low (warning) | ||
| 5134 | Unknown Shutdown at Idle | ||
| 5365 | Fault Code on Secondary Source (Information that the Fueling Has Been Shifted to Secondary Source) | ||
| 5669 | Engine Combustion (Shutdown) | ||
| 6518 | Cold Start Idle Active (Event) |
| Symptom | Cause | Remedy |
|---|---|---|
| Low AC Voltage at Startup | Loss of residual magnetism in the exciter stator lamination | Restore magnetism: attach leads to a 12VDC battery with a diode in one lead; run the generator at rated speed, no load; briefly (maximum one second) connect positive lead to control board terminal F1: P17-1 and negative lead to control board terminal F2: P17-2 |
| Unstable Voltage (No Load) | Engine governing unstable | Check for engine governor hunting with a frequency meter or tachometer, or cyclic irregularities in the engine with InPower; if any engine DTC fault codes are present, troubleshoot them using the E-Controls manual; check fuel supply pressure to ensure that it is consistent; ensure that the throttle assembly moves freely, clean it if necessary; check the spark plugs for buildup, ensure that a spark is present at each cylinder, repair or replace them if necessary; check for any exhaust restriction, clean or replace components as necessary; check for an intake leak, repair or replace components as necessary; check for proper function of the crankshaft and camshaft position sensors, and the wiring to the ECM from the sensors, repair or replace components as necessary; check the fuel mix control valve for proper operation, such that it can move freely and easily, clean or replace the valve if necessary |
| Unstable Voltage (No Load) | Loose or corroded connections | Check electrical connectors on terminals on the control board; check auxiliary terminals for loose connections; repair or replace as necessary |
| Unstable Voltage (No Load) | Intermittent ground on machine | Megger test all the windings, including the exciter stator; low insulation resistance can affect the PCC (disconnect the PCC before megger test) |
| Unbalanced Voltage (With Load) | Alternator loads unbalanced | Check that loads are balanced on each leg of alternator output (L1, L2, L3) |
| Unbalanced Voltage (With Load) | Engine governing unstable | Check for engine governor hunting with a frequency meter or tachometer, or cyclic irregularities in the engine with InPower; if any engine DTC fault codes are present, troubleshoot them using the E-Controls manual; check fuel supply pressure to ensure that it is consistent; ensure that the throttle assembly moves freely, clean it if necessary; check the spark plugs for buildup, ensure that a spark is present at each cylinder, repair or replace components as necessary; check for any exhaust restriction, clean or replace components as necessary; check for an intake leak, repair or replace components as necessary; check for proper function of the crankshaft and camshaft position sensors, and the wiring to the ECM from the sensors, repair or replace components as necessary; check the fuel mix control valve for proper operation, such that it can move freely and easily, clean or replace the valve if necessary |
| Unstable Voltage (With Load) | Engine governing unstable | Refer to the engine service manual (if applicable) or E-Controls service manual |
| Unstable Voltage (With Load) | Leading power factor load created by power factor correction capacitors | Isolate the power factor correction capacitors until sufficient motor load has been applied to counteract the leading power factor; adjust as required if corrects the issue |
| Unstable Voltage (With Load) | Fluctuations in load current (motor starting or reciprocating loads) | Check the load current on a stable supply (i.e., mains), or separately excite the machine; a variable DC supply is required for on load separate excitation tests |
| Unstable Voltage (With Load) | Automatic voltage regulator parameters configured incorrectly | Contact your local Cummins distributor |
| Poor Voltage Regulation (With Load) | Unbalanced load | Check voltage and load current on all phases; if unbalanced, redistribute the load more evenly across the phases |
| Poor Voltage Regulation (With Load) | Voltage drop between alternator and load, caused by losses in supply cable (power losses) | Check the voltage at both ends of the cable run at full load; large differences in voltages indicate a large volts drop along the cable; a larger diameter cable is required in severe cases |
| Poor Voltage Regulation (With Load) | Fault on main rectifier or excitation winding | Check the no load excitation voltage across automatic voltage regulator X+ (F1) and XX- (F2); voltage should be no higher than 12 VDC |
| Poor Voltage Regulation (With Load) | Under frequency roll-off protection activated | Under frequency roll-off protection is activated, indicating excessive load; check that under frequency roll-off set point and slope are correct |
| Engine Is Difficult to Start or Does Not Start | Battery voltage is low, interrupted, or open | Check the battery connections, unswitched battery supply circuit, and fuses; correct or replace if necessary |
| Engine Is Difficult to Start or Does Not Start | Fuel system issues | Verify fuel pressure at the generator set; inspect fuel lines and connections for leaks (spray soapy water along the lines and at connection, bubbling indicates a likely leak location), repair the leaks; open the manual fuel shutoff (FSO) valve if closed; check the FSO valve solenoids and circuit for proper operation, check for continuity and proper operation, correct or replace if necessary; examine the wiring to the throttle body for damage, check for DTC fault codes and troubleshoot as specified in the E-Controls manual, repair if necessary; check for fault codes using the E-Controls tool and troubleshoot as specified in the E-Controls manual, inspect the bore of the throttle body, clean if necessary or replace if worn; inspect the pressure regulator and EPR assembly for damage, the valve located inside the assembly should move freely, clean or replace if necessary |
| Engine Is Difficult to Start or Does Not Start | Air intake or exhaust issues | Check the air intake system restriction; clean or replace the air filter and inlet piping if necessary; check the exhaust system restrictions; correct or replace if necessary |
| Engine Is Difficult to Start or Does Not Start | Sensor issues | Check the intake manifold pressure sensor, correct or replace if necessary; refer to the Sensors section for the temperature manifold absolute pressure (TMAP) sensor; refer to the Control System section and/or the Sensors section for the crankshaft and/or camshaft speed/position sensors |
| Engine Is Difficult to Start or Does Not Start | Base engine problem | Check the engine for high crankcase pressure and low compression, as well as damaged pistons, camshaft, and other parts; correct or replace if necessary |
| Engine Experiences Low Power, Poor Acceleration, or Poor Response | Excessive load | Ensure that the load on the generator set does not exceed the generator set kW rating; revisit the generator set sizing process to ensure that the generator set is correctly sized for the application, especially if new loads have been introduced into the system |
| Engine Experiences Low Power, Poor Acceleration, or Poor Response | Fuel system issues | Inspect fuel lines, fuel connections, and fuel filters for leaks; repair if leaks are found; check the fuel shutoff valve solenoid and circuit |
| Engine Experiences Low Power, Poor Acceleration, or Poor Response | Air intake or exhaust issues | Check the air intake system for restriction; clean or replace the air filter and inlet piping as necessary; inspect the air intake and exhaust systems for air leaks; check the exhaust system for restrictions |
| Engine Experiences Low Power, Poor Acceleration, or Poor Response | Engine speed governor issue | Refer to the engine service manual |
| Engine Experiences Low Power, Poor Acceleration, or Poor Response | Other issues | The generator set is operating above recommended altitude: generator set power decreases above recommended altitude, refer to the Generator Set Data Sheet for the specific generator set for specifications; base engine problem: check the engine for high crankcase pressure and low compression, as well as damaged pistons, camshaft, and other parts, refer to the engine service manual; engine calibration values set in control are not correct: verify governor settings in control, if needed contact your service support representative |
| Engine Runs Rough or Misfires | Ignition system issues | Inspect the spark plugs, clean or replace the spark plugs if necessary; test the ignition coils using a coil on a plug tester (or in-line spark tester) to isolate the faulty coil, replace the faulty coil if necessary; check the coil wiring, inspect connectors and wires for breaks, and test continuity |
| Engine Runs Rough or Misfires | Engine air intake system or engine exhaust system issues | Check the air intake system for restriction; clean or replace the air filter and inlet piping as necessary; repair air intake system or exhaust system leaks if necessary; check the exhaust system back pressure; replace the exhaust system if necessary |
| Engine Runs Rough or Misfires | Fuel system issues | Inspect fuel lines and fuel connections for leaks; repair if leaks are found |
| Engine Runs Rough or Misfires | Other issues | Verify that the proper fuel type is selected; there is a base engine problem: check the engine for high crankcase pressure and low compression, as well as damaged pistons, camshaft, and other parts, correct or replace if necessary |
| Engine Shuts Off Unexpectedly or Dies during Deceleration | Emergency Stop (if used) | Make sure that the Emergency Stop circuit is not energized |
| Engine Shuts Off Unexpectedly or Dies during Deceleration | Fuel system issues | Check the fuel supply for appropriate pressure and flow; open the manual fuel shutoff (FSO) valve if closed; check the FSO valve solenoids and circuit, repair if necessary |
| Engine Shuts Off Unexpectedly or Dies during Deceleration | Wiring to the throttle body has failed (shorted or open) | Verify that the wiring is intact; repair if necessary |
| Engine Shuts Off Unexpectedly or Dies during Deceleration | Engine Control Module (ECM) related issues | Check the battery connections; check all components in the un-switched battery supply circuit to the ECM; check the grounding and verify the correct placement of the star washer on the engine block ground cable; check connections, wiring and components (i.e., relays) between the ECM and the PCC; correct or replace the ECM if necessary |
| Engine Shuts Off Unexpectedly or Dies during Deceleration | Base engine problem | Check the engine for high crankcase pressure and low compression, as well as damaged pistons, camshaft, and other parts; correct or replace if necessary |
| Engine Speed Surges Under Load or in Operating Range | Fuel system issues | Inspect fuel lines and connections for leaks (spray soapy water along the lines and at connection, bubbling indicates a likely leak location), repair if leaks are found; check for fault codes using the E-Controls tool and troubleshoot as specified in the E-Controls manual, inspect the bore of the throttle body, clean if necessary or replace if worn; inspect the pressure regulator and EPR assembly for damage, the valve located inside the assembly should move freely, clean or replace if necessary |
| Engine Speed Surges Under Load or in Operating Range | Sensor issues | Check for fault codes at the PCC; check for fault codes at the Engine Control Module (ECM); correct or replace if necessary |
| Engine Speed Surges Under Load or in Operating Range | Other issues | Dry the connectors with Cummins electronic cleaner, Part Number 3824510; check the engine for high crankcase pressure and low compression, as well as damaged pistons, camshaft, and other parts, correct or replace if necessary; temporarily disconnect the alternator and test-run the engine, replace the alternator if necessary |
| Poor Engine Transient Response | Excessive loads | Make sure that the load on the generator set does not exceed the generator set kW rating; re-visit the generator set sizing process to make sure that the generator set is correctly sized for the application, especially if new loads have been introduced into the system |
| Poor Engine Transient Response | Fuel system leaks | Inspect fuel lines, fuel connections, and fuel filters for leaks; repair if leaks found; refer to the procedures in the troubleshooting and repair manual for the specific engine |
| Poor Engine Transient Response | Air intake or exhaust issues | Inspect the air intake and exhaust systems for air leaks; check the air intake system for restriction, clean or replace the air filter and inlet piping as necessary; check the exhaust system for restrictions |
| Engine Does Not Crank in Remote Mode (No Fault Message) | Faulty remote start customer wiring | Reset the control; attempt to start and check for wiring connections; if ground is not present, isolate to the remote switch or customer wiring, repair if necessary |
| Engine Does Not Crank in Remote Mode (No Fault Message) | Bad starter relay, wiring issue, bad starter, or key switch relay | Inspect and test these components; correct and replace components if necessary |
| Engine Starts but Will Not Keep Running | Battery voltage is low, interrupted, or open | Check the battery connections, unswitched battery supply circuit, and fuses; correct or replace if necessary |
| Engine Starts but Will Not Keep Running | Run/Stop circuit issues | Check the alternator Run/Stop circuit; correct or replace if necessary |
| Engine Starts but Will Not Keep Running | Fuel system issues | Verify fuel pressure at the generator set; inspect fuel lines and connections for leaks (spray soapy water along the lines and at connection, bubbling indicates a likely leak location), repair leaks if found; open the fuel shutoff (FSO) valve if closed; check the FSO valve solenoids and circuit for proper operation, check for continuity and proper operation, correct or replace if necessary; examine the wiring to the throttle body for damage, check for DTC fault codes and troubleshoot as specified in the E-Controls manual, repair if necessary; check for fault codes using the E-Controls tool and troubleshoot as specified in the E-Controls manual, inspect the bore of the throttle body, clean if necessary, replace if worn; inspect the pressure regulator and EPR assembly for damage, the valve located inside the assembly should move freely, clean or replace if necessary |
| Engine Starts but Will Not Keep Running | Base engine problem | Check the engine for high crankcase pressure and low compression, as well as damaged pistons, camshaft, and other parts; correct or replace if necessary |
| Engine Will Not Shut Off | Run/Stop circuit issue | Check the alternator Run/Stop circuit; correct or replace if necessary |
| Fuel Consumption Is Excessive | Excessive loads | Make sure that the load on the generator set does not exceed the generator set kW rating; re-visit the generator set sizing process to make sure that the generator set is correctly sized for the application, especially if new loads have been introduced into the system; refer to the T-030 manual for proper generator set sizing and application |
| Fuel Consumption Is Excessive | Maintenance, repair or environmental effects | Evaluate the engine repair to determine its effect on fuel consumption, correct if necessary; check part numbers to make sure the correct parts were used, replace incorrect parts; check the oil level, verify the dipstick calibration and oil pan capacity, fill the system to the specified level; consider altitude and ambient air temperature when evaluating fuel consumption, refer to the specific Engine Data Sheets for altitude derate information |
| Fuel Consumption Is Excessive | Air intake or exhaust issues | Inspect the air intake and exhaust systems for air leaks; check the air intake system for a restriction, clean or replace the air filter and inlet piping if necessary |
| Fuel Consumption Is Excessive | Fuel system issues | Repair the leaks in fuel lines and/or fuel connections; check the fuel system pressure sensors (fueling/timing), including the camshaft sensor, fuel pressure sensors, throttle positions sensors, crankshaft sensor, O2 sensor, and TMAP sensors for proper operation, refer to the E-Controls manual for test methods for each device |
| Fuel Consumption Is Excessive | Crankshaft and/or camshaft speed/position sensors are reading incorrectly | Check the sensors; check for ECM fault codes related to these sensors; correct or replace if necessary |
| Fuel Consumption Is Excessive | Other issues | Check engine-driven units for correct operation; check the cooling fan for correct operation (with fan belt removed, the fan should spin freely by hand in both directions), correct or replace if necessary; check the engine for high crankcase pressure, low compression, damaged pistons, camshaft, and other parts, listen for unusual noises and inspect possible causes, analyze the oil and inspect the filters to locate an area of probable damage, correct or replace if necessary |
| Engine Noise Is Excessive | Air intake or exhaust leaks | Inspect the air intake and exhaust systems for air leaks; replace the muffler if necessary |
| Turbocharger noise | Excessive mechanical noise from the turbochargers | Inspect the turbochargers for excessive mechanical noise; replace them if necessary |
| Mechanical or internal component wear or damage | Internal engine damage | Analyze the oil and inspect the filters to locate an area of probable damage; inspect and further investigate area of probable damage |
| Mechanical or internal component wear or damage | Valvetrain components are damaged | Replace damaged components |
| Mechanical or internal component wear or damage | The vibration damper is damaged | Replace the vibration damper |
| Mechanical or internal component wear or damage | Main bearing or connecting rod bearing noise | The engine is damaged, and needs repair or replacement |
| Mechanical or internal component wear or damage | Flywheel or flexplate cap screws are loose or broken | Check the flywheel or flexplate and the mounting cap screws; tighten any loose screws; replace any broken screws |
| Mechanical or internal component wear or damage | Piston, piston rings, or cylinder liner is/are worn or damaged | Replace worn or damaged components |
| Alternator output (amps) not within 10% of rated output | Repair or replace the alternator; refer to the alternator manufacturer's instructions for repair procedures | |
| Low compression on a single cylinder | External cylinder head gasket leak | Perform a wet compression test with liquid soap to determine if there is an external cylinder head gasket leak; if so, replace the gasket with a new one |
| Low compression on a single cylinder | Leak to a coolant passage | Perform a wet compression test with liquid soap to determine if there is an external cylinder head gasket leak; if so, replace the gasket with a new one |
| Low compression on adjacent cylinders with no external cylinder head gasket leak | Head gasket is probably leaking between the cylinders | Oil the rings to increase the pressure; re-check the pressure; if the pressure has still not increased, replace the gasket with a new one |
| Defective memory block | Connect to the device using InPower version 10.0 or greater; In InPower, right click on the device, and select Initial Calibration (Recover Device) from the menu that appears; If the capture file for the device is available, select "overlay capture file". If not, select feature codes. Feature codes can be found on the nameplate of the device, located on the alternator housing; If the problem persists, contact the factory for support. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Documented causes: Lubricating oil level is low; External leak; Fault simulation is enabled or the threshold is set too high; Coolant temperature is above specification. See the table for the matching fixes.
Documented causes: High ambient temperature; Coolant level below specification; Damaged or obstructed cooling system components; Inaccurate coolant temperature sensor. See the table for the matching fixes.
Documented causes: Excessive loads; Maintenance, repair or environmental effects; Air intake or exhaust issues; Fuel system issues. See the table for the matching fixes.