Cummins/Onan DFCB troubleshooting: 114 fault codes and symptom-cause-remedy entries from the manufacturer's own service documentation.
Cummins/Onan DFCB — full specs, parts & maintenance.
All Cummins/Onan fault codes →
| Code | Meaning | Cause | Remedy |
|---|---|---|---|
| F01 | Generator does not start | Possible causes include low battery voltage, faulty starter motor, or incorrect wiring | Check the battery voltage; replace if necessary. Test the starter motor. Verify all connections are correct and secure. Refer to the fault code table for more details. |
| F02 | Generator produces insufficient power output | Possible causes include clogged air filter, low fuel level, or malfunctioning alternator | Clean or replace the air filter. Check the fuel level; refill if necessary. Inspect the alternator for any signs of damage or wear. Refer to the fault code table for more details. |
| F03 | Generator overheats | Possible causes include clogged cooling system, low coolant level, or malfunctioning thermostat | Clean the radiator fins and check for debris blockages. Check the coolant level; top up if necessary. Test the thermostat to ensure it is functioning correctly. Refer to the fault code table for more details. |
| F04 | Generator produces excessive noise during operation | Possible causes include loose engine components, worn-out bearings, or malfunctioning muffler | Inspect all moving parts and tighten any loose bolts. Replace worn-out bearings as needed. Check the muffler for damage; replace if necessary. Refer to the fault code table for more details. |
| F05 | Generator emits black smoke during operation | Possible causes include rich fuel mixture, clogged air filter, or malfunctioning fuel injection system | Adjust the fuel mixture according to the manufacturer’s specifications. Clean or replace the air filter. Inspect and clean the fuel injection system components. Refer to the fault code table for more details. |
| F06 | Generator produces blue smoke during operation | Possible causes include oil dilution, worn-out piston rings, or malfunctioning exhaust valve | Check the oil level; top up if necessary. Inspect the piston rings for wear and replace as needed. Test the exhaust valves to ensure they are functioning correctly. Refer to the fault code table for more details. |
| F07 | Generator produces white smoke during operation | Possible causes include coolant leakage, water in fuel system, or malfunctioning thermostat | Inspect the cooling system for any leaks; repair if necessary. Check the fuel system for signs of water contamination; replace fuel as needed. Test the thermostat to ensure it is functioning correctly. Refer to the fault code table for more details. |
| 212 | Shutdown lamp lights. MESSAGE: HIGH COOLANT TEMP 212 - SHUTDOWN | Indicates engine has overheated (coolant temperature has risen above the shutdown trip point: 223° F − standby / 215° F − primary) | Allow engine to cool down completely before proceeding with the following checks: a. Check coolant level and replenish if low. Look for coolant leakage and repair if necessary. b. Check for obstructions to cooling airflow and correct as necessary. c. Check fan belt and repair or tighten if necessary. d. Reset control and restart after locating and correcting problem. Contact an authorized service center if none of the above. |
| 213 | Warning lamp lights. MESSAGE: ENG COOLANT SENDER 213 - WARNING | Indicates that the resistance of the coolant temperature sender is out of range. Contact an authorized service center. | |
| 214 | Shutdown lamp lights. MESSAGE: LOW COOLANT LVL 214 - WARNING or LOW COOLANT LVL 215 - SHUTDOWN | Indicates engine coolant level has fallen below the trip point. Allow engine to cool down completely before proceeding. a. Check coolant level and replenish if low. Look for possible coolant leakage points and repair if necessary. b. Reset control and restart after locating and correcting problem. Contact an authorized service center. | |
| 220 | Shutdown lamp lights. MESSAGE: MAG PICKUP 220 - SHUTDOWN | Indicates mag pickup speed indication is not being sensed or does not match generator set output frequency. a. Restart and check RPM on the digital display. b. Contact an authorized service center. | |
| 221 | Shutdown lamp lights. Engine will not crank. MESSAGE: FAIL TO CRANK 221 - SHUTDOWN | Indicates possible fault with control or starting system. Check for the following conditions: a. Poor battery cable connections. Clean the battery cable terminals and tighten all connections. b. Discharged or defective battery. Recharge or replace the battery. c. Contact an authorized service center for service of starter and starting system. | |
| 222 | Shutdown lamp lights. Engine stops cranking. MESSAGE: OVERCRANK 222 - SHUTDOWN | Indicates possible fuel system problem. a. Check for empty fuel tank, fuel leaks, or plugged fuel lines and correct as required. b. Check for dirty fuel filter and replace if necessary. c. Check for dirty or plugged air filter and replace if necessary. d. Reset the control and restart after correcting the problem. Contact an authorized service center if none of the above. | |
| 223 | Shutdown lamp lights. Engine runs and then shuts down. MESSAGE: OVERSPEED 223 - SHUTDOWN | Indicates engine has exceeded normal operating speed. (2070 rpm @ 60 hz; 1800 rpm @ 50 hz) Contact an authorized service center. | |
| 230 | Warning lamp lights. MESSAGE: LOW DC VOLTAGE 230 - WARNING | Indicates battery voltage is below 24 VDC. a. Discharged or defective battery. Check the battery charger fuse. Recharge or replace the battery. b. Poor battery cable connections. Clean the battery cable terminals and tighten all connections. c. Contact an authorized service center if none of the above. | |
| 231 | Warning lamp lights. MESSAGE: HIGH DC VOLTAGE 231 - WARNING | Indicates battery voltage exceeds 32 VDC. Contact an authorized service center. | |
| 232 | Warning lamp lights. MESSAGE: WEAK BATTERY 232 - WARNING | Indicates battery voltage drops below 60% of nominal for two seconds, during starting. a. Discharged or defective battery. See Warning message 230, LOW DC VOLTAGE. | |
| 240 | Warning lamp lights. MESSAGE: LOW FUEL DAY 240 - WARNING | Indicates day tank fuel supply is running low. Check fuel supply and replenish as required. | |
| 241 | Warning lamp lights. MESSAGE: LOW FUEL 241 - WARNING | Indicates fuel supply is running low. Check fuel supply and replenish as required. | |
| 250 | Shutdown lamp lights. MESSAGE: EEPROM ERROR 250 - SHUTDOWN | Indicates PCC memory error. Data corruption of critical operating parameters. Contact an authorized service center. | |
| 251 | Warning lamp lights. MESSAGE: EEPROM ERROR 251 - WARNING or 252 - WARNING | Indicates PCC memory error. Data corruption of noncritical operating parameters. Contact an authorized service center. | |
| 260 | Shutdown lamp lights. MESSAGE: CUSTOMER FAULT 1 260 - SHUTDOWN or GROUND FAULT 261 - SHUTDOWN | ||
| 301 | HIGH AC VOLTAGE | Shutdown | |
| 303 | LOW AC VOLTAGE | Shutdown | |
| 313 | UNDER FREQUENCY | Shutdown | |
| 320 | OVERCURRENT | Warning | |
| 322 | SHORT CIRCUIT | Shutdown | |
| 330 | OVERLOAD | Warning | |
| 335 | REVERSE POWER | Shutdown | |
| 101 | Engine continues to operate at reduced RPM. | ||
| 200 | LOW OIL PRESSURE | Shutdown | |
| 201 | Engine oil pressure has dropped below the shutdown trip point. | Check oil level, lines and filters. If oil system is OK but oil level is low, replenish. Reset control and restart. | |
| 204 | Engine oil pressure sender is not functioning correctly. | Check that the engine oil pressure sender is properly connected. Contact an authorized service center. | |
| 210 | Low Engine Temp | Indicates engine coolant heater is not operating or is not circulating coolant. Check for the following conditions: a. Coolant heater not connected to power supply. Check for blown fuse or disconnected heater cord and correct as required. b. Check for low coolant level and replenish if required. Look for possible coolant leakage points and repair as required. c. Contact an authorized service center if none of the above. | |
| 211 | High Coolant Temp | Indicates engine has begun to overheat and coolant temperature has risen to an unacceptable level: (215° F − standby / 207° F − primary). | |
| 260 | Warning lamp lights. MESSAGE: CUSTOMER FAULT 1 | ||
| 261 | Warning lamp lights. MESSAGE: GROUND FAULT | ||
| 262 | Warning lamp lights. MESSAGE: RUPTURE BASIN | ||
| 263 | Warning lamp lights. MESSAGE: HIGH GEN TEMP | ||
| 301 | Shutdown lamp lights. MESSAGE: HIGH AC VOLTAGE | Indicates that one or more of the phase voltages has exceeded 130% of nominal, or has exceeded 110% of nominal for 10 seconds. Contact an authorized service center. | |
| 303 | Shutdown lamp lights. MESSAGE: LOW AC VOLTAGE | Indicates that one or more of the phase voltages has dropped below 85% of nominal for 10 seconds. Contact an authorized service center. | |
| 313 | Shutdown lamp lights. MESSAGE: UNDER FREQUENCY | Indicates that engine speed has dropped below 90% of nominal for 10 seconds. NOTE: Five seconds before shutdown, a Load Dump signal is initiated. Contact an authorized service center. | |
| 320 | Warning lamp lights. MESSAGE: OVERCURRENT | Indicates that generator output current has exceeded 110% of rated for 60 seconds. Contact an authorized service center. | |
| 321 | Shutdown lamp lights. MESSAGE: OVERCURRENT | Indicates that generator output current has exceeded 110% of rated, and that a PCC time/current calculation has initiated an overcurrent shutdown. Contact an authorized service center. | |
| 322 | Shutdown lamp lights. MESSAGE: SHORT CIRCUIT | Indicates that generator output current has exceeded 175% of rated. Contact an authorized service center. | |
| 330 | Warning lamp lights. MESSAGE: OVERLOAD | Indicates that three-phase power output exceeds 105% of standby (or 115% of prime) rating. After five seconds, the Load Dump output is activated. After 60 seconds, the OVERLOAD warning is activated. Contact an authorized service center. | |
| 335 | Shutdown lamp lights. MESSAGE: REVERSE POWER | Indicates improper CT or PT phasing. (Non-parallel units only.) Contact an authorized service center. | |
| 231 | Warning lamp lights. | Indicates battery voltage exceeds 32 VDC. Contact an authorized service center. | |
| 250 | Shutdown lamp lights. | Indicates PCC memory error. Data corruption of critical operating parameters. Contact an authorized service center. | |
| 102 | Engine shuts down and will not crank. | Indicates local or remote Emergency Stop. | To reset the local Emergency Stop button : Pull the button out or turn the switch clockwise (button with arrow) and allow it to pop out. Move the Run/Off/Auto switch to Off. Press the Reset switch. Select Run or Auto, as required. |
| 121 | Speed Signal Lost | ||
| 135 | Oil Pressure Sensor High | ||
| 141 | Oil Pressure Sensor Low | ||
| 143 | Pre-Low Oil Pressure Sensor | ||
| 144 | Coolant Temperature Sensor High | ||
| 145 | Coolant Temperature Sensor Low | ||
| 146 | Pre-High Cool Temp | ||
| 151 | High Coolant Temp | ||
| 197 | Low Coolant Level | ||
| 234 | Overspeed | ||
| 235 | Low Coolant Level | ||
| 359 | Fail to Start | ||
| 415 | Low Oil Pressure | ||
| 441 | Low Battery Voltage | ||
| 442 | High Battery Voltage | ||
| 1123 | Shutdown After Battle Short | ||
| 1124 | Delayed Shutdown | ||
| 1131 | Battle Short Active | ||
| 1244 | Engine Normal Shutdown | ||
| 1311 | Customer Inputs #1 | ||
| 1312 | Customer Inputs #2 | ||
| 1317 | Customer Inputs #3 | ||
| 1318 | Customer Inputs #4 | ||
| 1334 | Crit Scaler OR | ||
| 1335 | Non-Crit Scaler OR | ||
| 1416 | Fail to Shutdown | ||
| 1417 | Power Down Failure | ||
| 1433 | Emergency Stop | ||
| 1434 | Remote Emergency Stop | ||
| 1435 | Low Coolant Temperature | ||
| 1438 | Fail to Crank | ||
| 1442 | Weak Battery | ||
| 1443 | Battery Failed | ||
| 1444 | KW Overload | ||
| 1445 | Short Circuit | ||
| 1446 | High AC Voltage | ||
| 1447 | Low AC Voltage | ||
| 1448 | Under Frequency | ||
| 1449 | Over Frequency | ||
| 1461 | Loss of Field | ||
| 1466 | Modem Failure | ||
| 1468 | Network Error | ||
| 1469 | Speed/Hz Match | ||
| 1471 | Over Current | ||
| 1472 | Over Current | ||
| 2335 | Excitation Fault | ||
| 2336 | Memory Error | ||
| 2341 | High Control Temperature | ||
| 2342 | Too Long in Idle | ||
| 2967 | Governor Fault | ||
| 2968 | AVR Fault | ||
| 2969 | LON Failure | ||
| 2972 | Field Overload |
| Symptom | Cause | Remedy |
|---|---|---|
| Status Indicators are not functioning properly | Check the status indicators and ensure they are correctly connected. Refer to the troubleshooting table for further assistance. | |
| Line Circuit Breaker is tripped or malfunctioning | Reset the line circuit breaker if it has tripped. If the issue persists, refer to the troubleshooting table for further steps. | |
| Control and diagnostics via network or PC are not working | Ensure that the network connection is stable and correct. Check the control panel settings and software compatibility. Refer to the troubleshooting table for specific issues. | |
| Engine has shut down because of low oil pressure | Low Oil Pressure | This red lamp indicates the engine has shut down because of low oil pressure. |
| Engine has shut down because of excessive speed | Overspeed Shutdown | This red lamp indicates the engine has shut down because of excessive speed. |
| Engine failed to start | Fail to Start | This red lamp indicates the engine failed to start. |
| Engine starts from generator control panel but will not start automatically or from a remote panel. | (Note: The Run/Off/Auto switch must be in the Auto position for automatic or remote starting). Check the control wiring between the remote switch and the PCC. Contact an authorized service center. | |
| No AC output voltage. | Contact an authorized service center. | |
| Control does not power up when the Run/Off/Auto switch is set to Run or the Self Test switch is pressed. | There is no DC power to the control. | A. Check for battery disconnected, discharged, or improperly connected. b. Fuse F1 (20A/32V, Type 3AG) may be open. Replace with the same type. (Fuse is mounted near engine starter/solenoid, see Figure 4-2). Contact an authorized service center. |
| Warning, Shutdown, and Non-Automatic lamps are not lit. Digital display shows main menu or selected menu. | Indicates all engine systems are normal. No corrective action required | |
| Non-Automatic lamp flashes. | Indicates Run/Off/Auto switch is not in the Auto position. This will prevent automatic starting if an automatic transfer switch is used. | Move the Run/Off/Auto switch to the Auto position for automatic operation. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Documented causes: Possible causes include low battery voltage, faulty starter motor, or incorrect wiring. See the table for the matching fixes.
Documented causes: Possible causes include clogged air filter, low fuel level, or malfunctioning alternator. See the table for the matching fixes.
Documented causes: Possible causes include clogged cooling system, low coolant level, or malfunctioning thermostat. See the table for the matching fixes.