| 2 | Low Oil Pressure Fault | | |
| 3 | Service Check Fault | | |
| 4 | Overcrank | | |
| 12 | Overvoltage | | |
| 13 | Undervoltage | | |
| 14 | Overfrequency | | |
| 15 | Underfrequency | | |
| 17 | Fuel Pump Fault | | |
| 19 | Governor Actuator (EFI Only) | | |
| 22 | Governor Actuator Overload (EFI Only) | | |
| 23 | Oil Pressure Switch Fault | | |
| 27 | Voltage Sense Lost | | |
| 29 | High Battery Voltage | | |
| 31 | Overspeed Fault | | |
| 32 | Low Cranking Speed Sense | | |
| 33 | Fault Code 3 - Fault Code 33 | | |
| 35 | Control Card Failure | | |
| 36 | Generator Set Stopped Without Fault Condition - Fault Code 36 | | |
| 37 | Invalid Set Configuration | | |
| 38 | Field Overload (Overvoltage) | | |
| 41 | Alternator Rotor Fault | | |
| 42 | Processor Fault - Fault Code 42 | | |
| 43 | Processor Fault - Fault Code 43 | | |
| 45 | Speed Sense Fault | | |
| 47 | Ignition Fault | | |
| 48 | Field Sense Fault | | |
| 51 | Processor Failure - Fault Code 51 | | |
| 52 | Fuel Injector Fault (EFI Only) | | |
| 54 | MAT Sensor Fault (EFI Only) | | |
| 56 | MAP Sensor Fault (EFI Only) | | |
| 57 | Overprime Fault | | |
| CODE NO. 12 | OVERVOLTAGE SHUTDOWN—Controller unable to maintain rated voltage | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 13 | UNDERVOLTAGE SHUTDOWN—Controller unable to maintain rated voltage | | Corrective Action: Reduce the number of connected appliances, especially when air conditioners and battery chargers are running. |
| CODE NO. 14 | OVERFREQUENCY SHUTDOWN—Engine governor unable to maintain rated frequency | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 15 | UNDERFREQUENCY SHUTDOWN—Engine governor unable to maintain rated frequency | | Corrective Action: Reduce the number of connected appliances, especially when air conditioners and battery chargers are running. |
| CODE NO. 19 | GOVERNOR ACTUATOR SHUTDOWN—Controller sensed open or shorted circuit | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 22 | GOVERNOR ACTUATOR OVERLOAD SHUTDOWN—Duration of operation at or near full-duty cycle beyond design limit | | Corrective Action: Reduce the number of connected appliances, especially when air conditioners and battery chargers are running. Service the air cleaner (Page Section 4.5). Check for and repair a blocked exhaust system. |
| CODE NO. 23 | LOW OIL PRESSURE CUTOFF SWITCH SHUTDOWN—Controller sensed switch still open during start—not a running fault | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 27 | VOLTAGE SENSE SHUTDOWN—Controller unable to sense output voltage | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 29 | HIGH BATTERY VOLTAGE SHUTDOWN—Voltage across battery system greater than 19 volts | | Corrective Action: Check battery bank connections and reconnect if necessary so that the 12 volt batteries serving the genset are connected in parallel (12 volt) rather than in series (24 volt). Select a lower battery boost charge rate. |
| CODE NO. 31 | OVERSPEED SHUTDOWN—Engine speed greater than 3400 rpm | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 32 | LOW CRANKING SPEED SHUTDOWN—Cranking speed less than 180 rpm for more than 2 seconds | | Corrective Action: Clean and tighten the positive (+) and negative (-) battery cable connections at the battery and at the genset. Recharge or replace the battery. Refer to the battery manufacturer's recommendations. Replace engine oil with oil of proper viscosity for ambient temperatures (Page Section 2.5). (High oil viscosity can slow down cranking speed.) |
| CODE NO. 35 | CONTROL CARD FAILURE SHUTDOWN—Microprocessor EEPROM error during self-test | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 36 | ENGINE STOPPED SHUTDOWN—Engine stopped without command by controller | | |
| CODE NO. 37 | INVALID GENSET CONFIGURATION SHUTDOWN—Wrong frequency/rpm ratio | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 38 | OVERCURRENT (FIELD OVERLOAD) SHUTDOWN—Low power factor loads | | Corrective Action: Reduce the number of appliances running at the same time, especially those with high motor starting loads such as air conditioners. Have air conditioners and other appliances checked for proper operation. (A locked compressor rotor can cause very low power factor.) |
| CODE NO. 41 | GENERATOR ROTOR SHUTDOWN—Controller unable to sense field or output voltage | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 42 | PROCESSOR SHUTDOWN—Microprocessor ROM error during self-test | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 43 | PROCESSOR SHUTDOWN—Microprocessor RAM error during self-test | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 45 | SPEED SENSE SHUTDOWN—Controller unable to sense quadrature frequency | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 47 | IGNITION SHUTDOWN—Controller unable to sense ignition | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 48 | GENERATOR FIELD SENSE SHUTDOWN—Controller unable to sense field voltage | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 51 | PROCESSOR SHUTDOWN—Microprocessor malfunction | | Corrective Action: See an authorized Onan dealer. |
| CODE NO. 52 | FUEL INJECTOR SHUTDOWN | (Open or short circuit in fuel injector) | See an authorized Onan dealer. |
| CODE NO. 54 | MAT SENDER SHUTDOWN | (Open or short circuit in MAT sender) | See an authorized Onan dealer. |
| CODE NO. 56 | MAP SENDER SHUTDOWN | (Open or short circuit in MAP sender) | See an authorized Onan dealer. |
| CODE NO. 57 | OVERPRIME SHUTDOWN | (Prime mode exceeded 3 minutes) | Check for and remove any object that may be holding either control switch (remote or local) in the prime position. |
| CODE NO. 58 | Exhaust Gas Temp Shutdown/Fault | (Exhaust gas temperatures reach 650C (1202F) for 2 secs when the set is running) | See an authorized Onan dealer |
| 36 | Generator Set Stopped Without Fault Condition | | |
| 42 | Processor Fault | | |
| 51 | Processor Failure | | |
| 58 | Exhaust Gas Temperature Shutdown | | |
| 81 | Exhaust Gas Temperature Sensor Open | | |
| 82 | Exhaust Gas Temperature Sensor Shorted | | |