The DC Controls - 12-Volt System is a generator-set controller. It is used on generator sets from Cummins/Onan, including the HDKA.
| Code | Meaning | Cause | Remedy |
|---|---|---|---|
| -01 | Fuel level in coach tanks | Prime genset fuel system | |
| 1 | HIGH TEMPERATURE | (Engine coolant or inverter heat sink temperature exceeded design limit) | Check the second-level fault code by touching Stop. The second-level fault will be either No. 33 or No. 34. |
| 1, 2, 3, or 4 | First level faults | ||
| 11 | OVERCURRENT FAULT | (AC output short) | 1. Turn off the genset line circuit breaker. If the genset no longer shuts down, the genset is probably okay—check for and repair a short circuit in the vehicle appliances, wiring or shorted battery charger transformer. 2. Check whether the vehicle engine and genset share the same starting battery. If so, and this fault occurs when cranking the vehicle engine, low battery voltage may be causing this shutdown. Increase battery capacity or install a separate battery and battery charging system for the genset. |
| 12 | INVERTER OVERVOLTAGE FAULT | Check whether the vehicle engine and genset share the same starting battery. If so, and this fault occurs when cranking the vehicle engine, low battery voltage may be causing this shutdown. Increase battery capacity or install a separate battery and battery charging system for the genset. | |
| 13 | INVERTER UNDERVOLTAGE FAULT | Check whether the vehicle engine and genset share the same starting battery. If so, and this fault occurs when cranking the vehicle engine, low battery voltage may be causing this shutdown. Increase battery capacity or install a separate battery and battery charging system for the genset. | |
| 14 | INVERTER OVERFREQUENCY FAULT | Reduce the number of connected appliances, especially when air conditioners and battery chargers are running. | |
| 15 | INVERTER UNDERFREQUENCY FAULT | 1. Reduce the number of connected appliances, especially when air conditioners and battery chargers are running. 2. Have air conditioners and other appliances checked for proper operation. (A locked compressor rotor can cause very low power factor.) | |
| 19 | GOVERNOR ACTUATOR FAULT | See an authorized Onan dealer. | |
| 22 | GOVERNOR ACTUATOR OVERLOAD FAULT | Reduce the number of connected appliances, especially when air conditioners and battery chargers are running. | |
| 3 | SERVICE CHECK FAULT | (A second-level fault occurred) | Check the second-level fault code by touching Stop. The second-level fault will be one of the following in this table. |
| 33, 44 | Not assigned due to misinterpretation risk | ||
| 8 | OVERLOAD | Reduce load and restart | |
| Code 1 | Engine Over Temperature | ||
| Code 12 | Over Voltage | ||
| Code 13 | Under Voltage | ||
| Code 14 | Over Frequency | ||
| Code 15 | Under Frequency | ||
| Code 19 | Governor Actuator | ||
| Code 2 | Low Oil Pressure | ||
| Code 22 | Governor Actuator Overload | ||
| Code 27 | Voltage Sense | ||
| Code 3 | Service Check | ||
| Code 4 | Over Crank | ||
| Fault Code Blinking | Restoring Fault Code Blinking | ||
| NO. 23 | LOW OIL PRESSURE CUTOFF SWITCH FAULT | Corrective Action: See an authorized Onan dealer. | |
| NO. 24 | COOLANT TEMPERATURE SENDER FAULT | Corrective Action: See an authorized Onan dealer. | |
| NO. 25 | ENGINE ABOVE SPEED TARGET FAULT | Corrective Action: See an authorized Onan dealer. | |
| NO. 26 | ENGINE BELOW SPEED TARGET FAULT | Corrective Action: 1. Reduce the number of connected appliances, especially when air conditioners and battery chargers are running. 2. Prime the engine fuel system by holding the control switch down in its Stop position for at least 1 minute. | |
| NO. 27 | PMA SENSE LOST FAULT | Corrective Action: See an authorized Onan dealer. | |
| NO. 28 | DC SENSE LOST FAULT | Corrective Action: Open the circuit breaker. If the fault does not persist, check for and disconnect excessive loads from the genset before starting. | |
| NO. 29 | HIGH BATTERY VOLTAGE FAULT | Corrective Action: 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. 31 | OVERSPEED FAULT | Corrective Action: See an authorized Onan dealer. | |
| NO. 32 | LOW CRANKING SPEED FAULT | Corrective Action: 1. Replace Fuse F2 (starter solenoid) if blown (Page 7). 2. Clean and tighten the positive (+) and negative (−) battery cable connections at the battery and at the genset (Page 17). 3. Recharge or replace the battery. Refer to the battery manufacturer’s recommendations. 4. Replace the engine oil with oil of proper viscosity for the ambient temperature (Page 16). (High oil viscosity can slow cranking speed.) | |
| NO. 33 | HIGH ENGINE COOLANT TEMPERATURE FAULT | Corrective Action: 1. Check the engine coolant level and add coolant and repair leaks as necessary (Page 20). 2. Check for and remove any objects blocking the air inlet or outlet openings in the bottom of the genset. 3. Reduce the number of appliances connected at the same time. (Note that high altitude and high ambient temperature decrease engine cooling capacity.) 4. Clean and flush the cooling system to remove coolant passage fouling. 5. If the genset overheats only underway, see the coach manufacture regarding air baffles or other means to direct cooling air into the genset. | |
| NO. 34 | HIGH INVERTER TEMPERATURE FAULT | Corrective Action: 1. Check for and remove any objects blocking the air inlet or outlet openings in the bottom of the genset. 2. Reduce the number of appliances connected at the same time. (Note that high altitude and high ambient temperature decrease cooling capacity.) | |
| NO. 35 | CONTROL CARD FAILURE FAULT | Corrective Action: See an authorized Onan dealer. | |
| NO. 36 | ENGINE STOPPED FAULT | Corrective Action: 1. Check fuel level. (Note: The genset fuel pickup is probably higher than the vehicle engine pickup.) 2. Prime the engine fuel system by holding the control switch down in its Stop position for at least 1 minute. 3. Check the engine air filter and remove any blockage (Page 17). 4. Check for mechanical damage. | |
| NO. 37 | INVALID GENSET CONFIGURATION FAULT | Corrective Action: See an authorized Onan dealer. | |
| NO. 42 | PROCESSOR FAULT | Corrective Action: See an authorized Onan dealer. | |
| No. 33 | High temperatures and temperature rises indicate that warm discharge air is recirculating back into the genset compartment or that the inlet or outlet air opening is restricted. | Find out why and correct as necessary to meet the temperature specifications. | |
| No. 33-High Engine Coolant Temperature | Inlet Air Temperature Rise: The rise in inlet air temperature over ambient air temperature must not exceed 8° F (4.4° C). Oil Temperature Rise: The rise in engine oil temperature over ambient air temperature must not exceed 190° F (106° C). Maximum Coolant Temperature: Maximum coolant temperature is 230° F (110° C), at which point the genset will shut down | High temperatures and temperature rises. indicate that warm discharge air is recirculating back into the genset compartment or that the inlet or outlet air opening is restricted. | Find out why and correct as necessary to meet the temperature specifications. |
| blink-blink-blink-blink-blink-pause-blink-blink-blink-blink-blink-blink-long pause-repeat | Cranking time exceeded 35 seconds | ||
| blink-blink-blink-blink-pause-blink-blink-blink-blink-blink-blink-long pause-repeat | Shutdown due to a service fault | Press Stop once to cause the two-digit, second-level shutdown code to blink. (Pressing Stop again will stop the blinking.) The two-digit code consists of 1, 2, 3, 4 or 5 blinks, a brief pause, and then 1 to 9 blinks. The first set of blinks represents the tens digit and the second set of blinks the units digit of the shutdown code number. | |
| blink-blink-blink-pause-blink-blink-blink-blink-blink-blink-long pause-repeat | Shutdown due to high engine coolant temperature | ||
| blink-blink-pause-blink-blink-blink-blink-blink-blink-long pause-repeat | Shutdown due to a loss of engine oil pressure |
| Symptom | Cause | Remedy |
|---|---|---|
| Blocked air inlet | Service as necessary. | |
| Damage to equipment and fire | Interconnections without an approved switching device | Use an approved switching device |
| Dizziness | Get out into the fresh air immediately. If symptoms persist, seek medical attention. Shut down the unit and do not operate until it has been inspected and repaired. | |
| ENGINE CRANKS WHEN BATTERY CONNECTED | Faulty Start Switch or grounded wiring | Corrective Action: See an authorized Onan dealer. |
| ENGINE DOES NOT CRANK | Tripped DC control breaker, Low cranking voltage | Reset the control breaker handle, Have the genset serviced if it keeps tripping. Clean and tighten or replace the positive (+) and negative (−) battery cable connectors and cables at the battery and the genset, Recharge or replace the battery |
| ENGINE LACKS POWER OR UNSTABLE | Inadequate fuel delivery, Contaminated fuel | Check for fuel (air) leaks at all fittings and tighten as necessary, Replace the fuel filter (p. 16), Connect the fuel lift pump to a container of fuel of known quality, Replace the contents of the fuel supply tank if there is a noticeable difference in performance |
| ENGINE WON’T CRANK—FUEL PUMP WON’T STOP | Faulty Stop Switch or grounded wiring | Corrective Action: See an authorized Onan dealer. |
| Engine Unstable (Hunts) | -Check: Fuel supply -Check: Fuel Lines for leakage -Check: Loose wire connection -Perform checks in step 01 -Check: Governor for binding -Check: Governor adjustments | |
| Engine Will Not Shut Off | -Check: Binding in the governor -Check: Actuator adjustment | |
| Engine cranks but does not start | Incorrect fuel? See Operator’s Manual recommendations. Check fuel system: fuel tank level, shut-off valves, fuel lines and connections, fuel filters, fuel pump and injection pump. Okay? Does K14 fuel solenoid energize when S11 is in Start position? | Check B+ circuit through S11. Test S11 per Checkout [G]. Test K14 per Checkout [F]. Check switch S11 per Checkout [G]. Check heater relay per Checkout [E]. Check heater wiring. |
| Engine does not crank. | Follow the troubleshooting procedure in Flow Chart A. | |
| Engine exhaust could ignite grass or brush | Parked in high grass or brush | |
| Engine not getting fuel | A. Open any closed shutoff valve. b. Check fuel level and refill as necessary. c. Prime the fuel system (p.12). d. Check for fuel (air) leaks at all fittings and tighten as necessary. e. Replace the fuel filter (p. 16). | |
| Engine starts but stops after running several seconds | Is a fault condition indicated by fault breaker CB12 on control panel? Check for a possible fault condition. If none, check fault monitors S1 through S4 and fault breaker CB12 for improper wiring. Check relay K12 per Checkout [H]. Is K12 good? Does DC control breaker trip after generator set is started? | Check for closing of S6 power latch switch. If switch is OK, check mechanical adjustment of K1 solenoid: is rod adjusted to correct length to allow the hold-in coil of K1 to latch? If K1 adjustment is OK and problem remains, replace engine monitor PC board. Check all B+ wiring for shorts to ground. Check fuel solenoid adjustment. |
Fault codes and symptom→remedy steps extracted from this controller’s service/owner documentation; verify against the official manual before servicing. Aggregated from the service documentation of generator sets built on this controller.