The Magnum Digital (MDC) is a generator-set controller. It is used on generator sets from John Deere, Magnum and Marathon, including the MMG100, MMG100C Super Start, MMG235 Super Start and MMG25FHICAN6.
Used across brands: John Deere, Magnum, Marathon
Also fitted to: John Deere MD, Magnum MMG35D Super Start (SS), Magnum MMG45K Super Start (SS), Magnum MMG55D Super Start (SS), Marathon 282CSL1505 (X).
| Code | Meaning |
|---|---|
| FC | ECU alarm FailureCode |
| SD | Sensor fail (FLS) |
| Sd Gen L1 <V | Shutdown Generator Line 1 Voltage Irregularity |
| Sd Gen L2 <V | Shutdown Generator Line 2 Voltage Irregularity |
| Sd Gen L3 <V | Shutdown Generator Line 3 Voltage Irregularity |
| WRN | Warning (WRN) |
| null | The door covering the customer connection lugs/cam lock receptacles is opened. |
| Symptom | Cause | Remedy |
|---|---|---|
| Engine exceeds normal operating temperature | Automatic shutdown system will stop the engine | |
| Engine shutdown | Fuel tank running dry, oil pressure less than 20 psi, coolant level low, high coolant temperature | Check fuel level and add if necessary; check for leaks; inspect engine for damage; check oil level and add if necessary; visually inspect engine for leaks; check coolant level and add if necessary; check radiator hoses, engine block, water pump for leaks; check oil to ensure no coolant mixed in; allow engine to cool before checking |
| HIGH COOLANT TEMPERATURE SHUT DOWN | Coolant temperature is 230°F (110°C) or more. | Check coolant level, add if necessary. Inspect for leaks. Check radiator shroud and ducting. Adjust water pump belt tension. |
| HIGH COOLANT TEMPERATURE SHUTDOWN | Coolant temperature is 230°F (110°C) or more. | Check coolant level, remove any blockages, inspect hoses and components for leaks, check water pump belt tension, and load the unit to prevent overheating. |
| High Coolant Temperature Shut down | Check the coolant level in the overflow jug. Restart the engine and read the coolant temperature to verify High Coolant Temperature Shut down. Stop the engine immediately if the coolant temperature is 230°F (110°C) or more. Allow the engine to cool. Add coolant to the overflow jug if it is low and then check the level of coolant in the radiator. To access the radiator cap, you must remove the access panel from the top of the enclosure directly above the radiator. Add coolant until it is 3/4” below the filler neck. Secure the radiator cap back into its original position. Check the radiator shroud and ducting for blockage and remove any foreign matter. Inspect coolant hoses, engine block and water pump for visible leaks. | |
| High Coolant Temperature shut down | 1. Check the coolant level in the overflow jug. 2. Restart the engine and read the coolant temperature to verify High Coolant Temperature shut down. Stop the engine immediately if the coolant temperature is 230°F (110°C) or more. 3. Allow the engine to cool. Add coolant to the overflow jug if it is low and then check the level of coolant in the radiator. To access the radiator cap, you must remove the access panel from the top of the enclosure directly above the radiator. Add coolant until it is 3/4 in (2 cm) below the filler neck. Secure the radiator cap back into its original position. 4. Check the radiator shroud and ducting for blockage and remove any foreign matter. 5. Inspect coolant hoses, engine block and water pump for visible leaks. 6. Check the tension of the serpentine drive belt for the water pump. 7. If no other problems are found, remove the load on the generator and restart the engine. Check the coolant temperature and shut the engine down immediately if it starts to overheat. | |
| Indicator light does not come on | Ballast may need to be serviced; check bulb or mast wiring | |
| LOW COOLANT LEVEL SHUT DOWN | Coolant level in the radiator is low. | Allow engine to cool. Check coolant level in the radiator. Access the radiator cap by removing the access panel from the top of the enclosure. |
| LOW COOLANT LEVEL SHUTDOWN | Coolant level in the radiator is low. | Check coolant level, inspect hoses, engine block, water pump for leaks, and check oil for coolant contamination. |
| LOW FUEL LEVEL SHUT DOWN | Fuel level is low or fuel tank has leaks. | Check the fuel level on the LCD window. Ensure no leaks in the fuel tank. Check the fuel level sender and connecting wiring for damage. |
| LOW FUEL LEVEL SHUTDOWN | Fuel level in the tank is low or fuel lines are running dry. | Check and refill the fuel level. Inspect for leaks and check the fuel level sender. |
| LOW OIL PRESSURE SHUT DOWN | Oil pressure is less than 20 psi (138 kPa). | Check the engine oil level with a dipstick. Visually inspect for oil leaks. If oil level is good, restart and verify oil pressure within five seconds. Check the oil pressure sender. |
| LOW OIL PRESSURE SHUTDOWN | Oil pressure is less than 20 psi (138kPa). | Check the engine oil level with a dipstick. Add oil if required. Visually inspect for oil leaks. If oil level is good, restart and verify loss of oil pressure. Check the oil pressure sender. |
| Lights are not illuminated when indicator light comes on and stays lit | Check bulb or the mast wiring | |
| OVERCRANK SHUT DOWN | Engine will not start. | Check fuel level, fuel pump operation, air filter for blockage. Refer to engine manual for additional troubleshooting. |
| OVERCRANK SHUTDOWN | Engine will not start. | Check fuel level, fuel pump operation, air filter for blockage. Refer to manual for additional troubleshooting. |
| OVERSPEED OR UNDERSPEED SHUT DOWN | Engine speed is above or below 60.0 Hz. | Disconnect loads and check frequency. Adjust engine speed as needed. |
| OVERSPEED OR UNDERSPEED SHUTDOWN | Engine speed is above or below 60.0 Hz. | Disconnect loads and adjust engine speed as needed based on manual instructions. |
| Oil pressure drops too low | Automatic shutdown system will stop the engine | |
| Overcrank Shut down | Check the fuel level in the tank. Check for proper operation of the fuel pump. Check air filter for blockage. If the engine will not start, consult the engine operation and maintenance manual for additional information on troubleshooting starting problems. | |
| Overcrank shut down | 1. Check the fuel level in the tank. 2. Check for proper operation of the fuel pump. 3. Check air filter for blockage. 4. If the engine will not start, consult the engine operation and maintenance manual for additional information on troubleshooting starting problems. | |
| Overspeed or Underspeed Shut down | Disconnect all loads and restart the generator. Read the frequency (Hz) on the LCD display. With no loads on the generator, the frequency should read 60.0 Hz. If the frequency is above or below 60.0 Hz, the engine speed will have to be adjusted. See the engine manual for throttle adjustments on mechanically governed units and see the electronic governor manual for electronically controlled units. | |
| Overspeed or underspeed shut down | 1. Disconnect all loads and restart the generator. Read the frequency (Hz) on the LCD display. With no loads on the generator, the frequency should read 60.0 Hz. 2. If the frequency is above or below 60.0 Hz, the engine speed will have to be adjusted. See the engine manual for throttle adjustments on mechanical governed units and see the electronic governor manual for electronically controlled units. |
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.