| 21 | Starter Solenoid Circuit - controller senses a short circuit | | - Check Connections at starter motor - Shorts and/or grounds at solenoid |
| 22 | Governor Actuator Overload - duration of operation at or near full-duty cycle is beyond the design limit | | - Check Load - Air intake restriction - Exhaust restriction - Air leak in fuel system |
| 23 | Low Oil Pressure Cutoff Switch | | |
| 24 | Temperature Sending Unit | | |
| 27 | AC Output Sense Fault | | |
| 28 | Quadrature Sense Fault | | |
| 29 | High Battery Voltage | | |
| 35 | Control Card | | |
| 36 | Engine Stopped Fault | | |
| 37 | Invalid Genset Configuration | | |
| 38 | Field Overload | | |
| 45 | Speed Sense Fault | | |
| 23 | Low Oil Pressure Cutoff Switch fault | | -Check -Perform fuel flow test -Governor linkage for binding -High idle adjustment -Injectors -Injection pump timing -Compression |
| 24 | Temperature Sending Unit fault | | -Check -Connections in wiring harness -Switch continunity |
| 35 | Control Card fault | | -Check -Control |
| 45 | Speed Sense Fault−controller does not sense quadrature frequency and voltage | | -Check -F2 Fuse -Starter circuits -K2 relay and connections -Rotor/stator windings for opens/shorts/ grounds |
| 010 | External Coolant Loss | | -Visually check for: -Coolant level is OK -Cracked or leaking hoses -Loose clamps -Leaks or defects in radiator -Coolant in oil |
| 47 | Excessive White Exhaust Smoke at Start-up (Warm Engine) | | -Check: -Glow plug operation -Low engine operating temperature -Valve settings -Air leaks in fuel system |
| 48 | Excessive White Exhaust Smoke at Start-up (Cold Engine) | | -Check: -Glow plug operation -Air leak in fuel system -Valve settings |
| Engine Cranks but will not Start | Engine Cranks but will not Start | | |
| E-DEAD STATUS INDICATOR LIGHT | Poor connections, faulty wiring or dead battery | | 1. Try starting the genset at the operator’s console if it does not start at the remote panel. 2. Clean and tighten the battery cable connections at the battery and at the genset. 3. Recharge or replace the battery. Refer to the battery manufacturer’s recommendations. |
| NO. 22 | GOVERNOR OVERLOAD FAULT—The duration of operation at or near full-duty cycle was beyond the design limit | | 1. Reduce the number of appliances running at the same time, especially those with high motor starting loads such as air conditioners. 2. Check for fuel (air) leaks at all fuel fittings and tighten as necessary. Prime the engine fuel system by holding the control switch at Stop for one minute. 3. Replace the engine air filter (Page 17) and clean the spark-arrest muffler (Page 18). 4. Replace the fuel filter (Page 19). |
| NO. 24 | TEMPERATURE SENDER FAULT—The controller sensed that the sender circuit is either open or shorted | | See an authorized Onan dealer. |
| NO. 27 | AC VOLTAGE SENSE FAULT—The controller was unable to sense output voltage | | See an authorized Onan dealer. |
| NO. 29 | HIGH BATTERY VOLTAGE FAULT—The controller sensed battery system voltage greater than 19 volts | | 1. 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). 2. Select a lower battery booster charge rate. |
| NO. 32 | LOW CRANKING SPEED FAULT—Cranking speed less than 100 rpm [2.5 Hz, generator] for more than 12 seconds | | 1. Have the vehicle propulsion engine running while trying to start the genset. (The battery charging alternator may be able to maintain starting voltage high enough to get the genset started.) 2. Clean and tighten the battery cable connections at the battery and at the genset. 3. Recharge or replace the battery. Refer to the battery manufacturer’s recommendations. 4. Replace engine oil with oil of proper viscosity for ambient temperatures. (High oil viscosity can slow down cranking speed.) |
| NO. 35 | CONTROL CARD FAULT—Microprocessor EEPROM error during self-test | | See an authorized Onan dealer. |
| NO. 36 | ENGINE STOPPED FAULT—The genset stopped without a command from the controller | | 1. Check the fuel level and refill as necessary. (Note: The genset fuel pickup is probably higher than the vehicle engine fuel pickup.) 2. Check for fuel (air) leaks at all fuel fittings and tighten as necessary. Prime the engine fuel system by holding the control switch at Stop for one minute. 3. Check the engine air filter (Page 17) and remove any blockage. 4. Check for mechanical damage. 5. Replace the fuel filter (Page 19). |
| NO. 38 | FIELD OVERLOAD FAULT—Field voltage exceeded 150 VDC | | 1. Reduce the number of air conditioners running at the same time (and other appliances that cause low power factor). 2. Have the air conditioners and other appliances checked for proper operation. (A locked compressor rotor can cause very low power factor.) |
| NO. 41 | SHORTED ROTOR FAULT—The rotor circuit is shorted to ground | | See an authorized Onan dealer. |
| NO. 42 | PROCESSOR FAULT—Microprocessor ROM error during self-test | | See an authorized Onan dealer. |
| NO. 43 | PROCESSOR FAULT—Microprocessor RAM error during self-test | | See an authorized Onan dealer. |
| NO. 45 | SPEED SENSE FAULT—Controller unable to sense quadrature frequency | | Check the fuel level and fill as necessary. Then prime the engine fuel system by holding the control switch at Stop for one minute and try restarting. |
| NO. 57 | OVERPRIME FAULT—Prime mode exceeded 3 minutes | | Check for and remove any object that may be holding either control switch (remote or local) in the prime (stop) position. |
| blink-blink-blink-pause-blink-blink-blink-blink-blink-blink-long pause-repeat | Shutdown due to high temperature | | |
| blink-blink | Shutdown due to a loss of engine oil pressure | | |
| blink-blink-blink-pause-1 to 9 blinks | Service fault | | |
| blink-blink-blink-blink | Cranking exceeded a preset time without starting | | |
| 2 | High temperature fault—CODE NO. 1 | (The engine coolant temperature exceeded 230° F [110° C]) | 1. Check the engine coolant level and add coolant as necessary. 2. Check for and remove any objects blocking the air inlet or outlet openings in the bottom of the genset. 3. Watch the temperature gauge (optional) and run fewer appliances at the same time to keep down the engine temperature. |
| 2 | Low oil pressure fault—CODE NO. 2 | (The low oil pressure cutoff switch closed for more than 10 seconds) | 1. Check the engine oil level and add oil as necessary. 2. Drain the excess oil if the oil level is above the Full mark on the dipstick. (The oil will foam if the level is too high and result in possible loss of oil pressure.) |
| 3 | Service check—CODE NO. 3 | (A second-level fault occurred) | Check the second-level fault code by momentarily pressing Stop. The second-level fault will be one of the following in this table. |
| 12 | Overvoltage fault—CODE NO. 12 | (The controller is not able to regulate to rated voltage) | See an authorized Onan dealer. |
| 13 | Undervoltage fault—CODE NO. 13 | (The controller is not able to regulate to rated voltage) | Turn OFF the line circuit breaker on the operator’s console. If the genset now runs, run it with fewer connected loads. |
| 14 | Overfrequency fault—CODE NO. 14 | (The controller is not able to regulate to rated frequency) | 1. Prime the engine fuel system by holding the control switch at Stop for one minute. (There may be air in the fuel system.) 2. Check for a tripped genset circuit breaker, reset it if necessary, and run with fewer connected loads. |
| 15 | Underfrequency fault—CODE NO. 15 | (The controller is not able to regulate to rated frequency) | 1. Turn OFF the line circuit breaker on the operator’s console. If the genset now runs, run it with fewer connected loads. 2. Prime the engine fuel system by holding the control switch at Stop for one minute. (There may be air in the fuel system.) |
| 21 | Starter solenoid circuit protection fault—CODE NO. 21 | (The controller sensed a starter control circuit short) | See an authorized Onan dealer. |
| 22 | Governor actuator overload fault—CODE NO. 22 | (The duration of operation at or near full-duty cycle was beyond the design limit) | 1. Reduce the number of appliances running at the same time. 2. Replace the engine air filter and clean the spark-arrest muffler. 3. Replace the engine fuel filter. |
| 23 | Low oil pressure cutoff switch fault—CODE NO. 23 | (The controller sensed a defective switch) | See an authorized Onan dealer. Also see BYPASSABLE FAULTS (Page 20). |
| 24 | Coolant temperature sender fault—CODE NO. 24 | (The controller sensed a defective sender) | See an authorized Onan dealer. Also see BYPASSABLE FAULTS (Page 20). |
| 27 | Quadrature sense fault—CODE NO. 27 | (The controller was unable to sense the required parameter) | See an authorized Onan dealer. |
| 28 | AC output sense fault—CODE NO. 28 | (The controller was unable to sense the required parameter) | See an authorized |
| 1 | The status indicator light is dead (There is no response to the control switch) | | 1. Try starting the genset at the operator’s console if it does not start at the remote panel. 2. Check whether Fuse F1 is blown. If it is, first check the battery connections for proper polarity: battery positive (+) to genset positive (+) and battery negative (–) to genset negative (–). If necessary, reconnect the battery cables properly and replace the fuse. (The control circuit is designed so that the fuse will blow if battery polarity is wrong.) 3. Clean and tighten the positive (+) and negative (–) battery cable connections at the battery and at the genset. 4. Recharge or replace the battery. Refer to the battery manufacturer’s recommendations. |
| CODE NO. 35 | CONTROL CARD FAULT—There was a memory error in the microprocessor during self-test | | See an authorized Onan dealer. |
| CODE NO. 37 | INVALID GENSET CONFIGURATION—There was a memory error in the microprocessor during self-test | | See an authorized Onan dealer. |
| CODE NO. 38 | FIELD OVERCURRENT FAULT—Too many low-power-factor-causing loads were connected | | 1. Reduce the number of air conditioners running at the same time (and other appliances that cause low power factor). 2. Have the air conditioners and other appliances checked for proper operation. (A locked compressor rotor can cause very low power factor.) |
| CODE NO. 45 | SPEED SENSE FAULT—The controller failed to sense quadrature frequency and voltage during cranking | | See an authorized Onan dealer. |