Northern Lights NL445D troubleshooting: 78 symptom-cause-remedy entries from the manufacturer's own service documentation.
Northern Lights NL445D — full specs, parts & maintenance.
| Symptom | Cause | Remedy |
|---|---|---|
| Starter inoperative | Check DC circuit breaker | If the breaker is tripped, reset it. |
| Starter inoperative | Loose or corroded connections | Clean and tighten loose battery and harness plug connection. |
| Starter inoperative | Low battery output | Check specific gravity of each battery; Check electrolyte level of each battery. |
| Starter inoperative | Defective electrical system ground wire | Repair or replace. |
| Starter cranks slowly | Low battery output | Battery is too small; Battery cables are too small; Check specific gravity of each battery; Replace battery if necessary; Check electrolyte level of each battery; If low, fill cells with distilled water. |
| Starter cranks slowly | Crankcase oil too heavy | Fill with oil of appropriate viscosity. |
| Starter cranks slowly | Loose or corroded connections | Clean and tighten loose connections. |
| Entire electrical system does not function | Check DC circuit breaker | If breaker is tripped, reset it. |
| Entire electrical system does not function | Faulty connection | Clean and tighten battery and harness plug connections. |
| Entire electrical system does not function | Sulfated or worn out batteries | Check specific gravity and electrolyte level of each battery. |
| Engine hard to start or will not start | Improper starting procedure | See starting section of this manual. Take special note of Bypass Switch operations. |
| Engine hard to start or will not start | No fuel | Check level of fuel in fuel tank. |
| Engine hard to start or will not start | Low battery output | Check electrolyte level and specific gravity of battery. |
| Engine hard to start or will not start | Excessive resistance in starting circuit | Clean and tighten all battery connections. |
| Engine hard to start or will not start | Crankcase oil too heavy | Use oil of proper viscosity. |
| Engine hard to start or will not start | Improper type of fuel | Consult fuel supplier and use proper type of fuel for operating conditions. |
| Engine hard to start or will not start | Water, dirt, or air in fuel system | Drain, flush, fill, and bleed system. |
| Engine hard to start or will not start | Clogged primary fuel filter element | Clean or replace filter element. |
| Engine hard to start or will not start | Clogged secondary fuel filter element | Replace filter element. |
| Engine hard to start or will not start | Dirty or faulty injection nozzles | Have your dealer check injection nozzles. |
| Lack of engine power | Engine overload | Reduce load. |
| Lack of engine power | Intake air restriction | Service air cleaner. |
| Lack of engine power | Clogged primary fuel filter element | Clean or replace filter element. |
| Lack of engine power | Clogged secondary fuel filter element | Replace secondary filter element. |
| Lack of engine power | Improper type of fuel | Consult supplier and use proper type of fuel for operating conditions. |
| Lack of engine power | Overheated engine | See “Engine Overheats” in next category. |
| Lack of engine power | Below normal engine temperature | Remove and check thermostat. |
| Lack of engine power | Improper valve clearance | Reset valves. Best done by dealer. |
| Lack of engine power | Dirty or faulty injection nozzles | Replace injectors. Best done by dealer; See your local dealer. |
| Lack of engine power | Injection pump out of time | See your local dealer. |
| Lack of engine power | Turbocharger malfunction | Stop the engine; Remove the air cleaner; Make sure the compressor wheel is stationary and then rotate it with your hand to see whether it is stiff to rotate; First rotate the wheel under light pressure, then by lightly pulling axially. If the wheel is stiff to rotate, the blades are damaged, or the blades hit the housing, the turbocharger should be replaced as soon as possible. |
| Engine runs irregularly or stalls frequently | Below normal engine temperature | Remove and check thermostat. |
| Engine runs irregularly or stalls frequently | Clogged primary fuel filter element | Clean or replace filter element. |
| Engine runs irregularly or stalls frequently | Clogged secondary fuel filter element | Replace secondary filter element. |
| Engine runs irregularly or stalls frequently | Water or dirt in fuel system | Drain, flush, fill, and bleed system. |
| Engine runs irregularly or stalls frequently | Dirty or faulty injection nozzles | Have your dealer check injection nozzles. |
| Engine runs irregularly or stalls frequently | Air in fuel system | Inspect clamps and hoses on suction side of fuel pump for air leak. |
| Engine runs irregularly or stalls frequently | Improper type of fuel | Consult fuel supplier and use proper type of fuel for operating conditions. |
| Engine overheats | Engine overloaded | Reduce load. |
| Engine overheats | Low coolant level | Fill tank or radiator to proper level; Check hoses for loose connections and leaks. |
| Engine overheats | Cooling system needs flushing | Flush cooling system. |
| Engine overheats | Defective thermostat | Remove and check thermostat. |
| Engine overheats | Defective temperature gauge/sender | Check water temperature with thermometer and replace gauge or sender if necessary. |
| Engine knocks | Insufficient oil | Check dipstick. |
| Engine knocks | Injection pump out of time | Call your dealer. |
| Engine knocks | Below normal engine temperature | Call your dealer. |
| Engine knocks | Engine overheating | Check your thermostat; Check water temperature to see if temperature gauge is working properly; See “Engine Overheating” section. |
| High fuel consumption | Improper type of fuel | Use correct fuel for temperature. |
| High fuel consumption | Clogged or dirty air cleaner | Service air cleaner. |
| High fuel consumption | Engine overload | Reduce load. |
| High fuel consumption | Improper valve clearance | See your local dealer. |
| High fuel consumption | Injection nozzles dirty | See your local dealer. |
| High fuel consumption | Injection pump out of time | See your local dealer. |
| High fuel consumption | Engine not at proper temperature | Check your thermostats; Check water temperature with thermometer and replace gauge if necessary. |
| High fuel consumption | Defective turbocharger | See your local dealer. |
| Below normal engine temperature | Thermostat not working properly | Check thermostat. |
| Below normal engine temperature | Temperature gauge not working properly | Check water temperature with thermometer and replace gauge if necessary. |
| Low oil pressure | Low oil level | Fill crankcase to proper level. |
| Low oil pressure | Improper type of oil | Drain and fill crankcase with correct oil. |
| Low oil pressure | Partially plugged oil filter | Replace filter. |
| High oil consumption | Break-in period | Oil consumption decreases after break-in. |
| High oil consumption | Crankcase oil too light | Use proper viscosity oil. |
| High oil consumption | Oil leaks | Check for leaks in lines around gaskets and drain plug. |
| High oil consumption | Restricted crankcase vent tube | Clean the vent tube. |
| High oil consumption | Engine overheats | See “Engine Overheats” in previous category. |
| High oil consumption | Defective turbocharger | See your local dealer. |
| Engine emits black or gray exhaust smoke | Clogged or dirty air cleaner | Service air cleaner. |
| Engine emits black or gray exhaust smoke | Defective muffler (back pressure too high) | Have dealer check back pressure. |
| Engine emits black or gray exhaust smoke | Improper fuel | Use correct fuel for temperature. |
| Engine emits black or gray exhaust smoke | Engine overload | Reduce load. |
| Engine emits black or gray exhaust smoke | Injection nozzles dirty | See your local dealer. |
| Engine emits black or gray exhaust smoke | Engine out of time | See your local dealer. |
| Engine emits black or gray exhaust smoke | Defective turbocharger | See your local dealer. |
| Engine emits white exhaust smoke | Improper fuel | Use correct fuel for temperature. |
| Engine emits white exhaust smoke | Cold engine | Warm up engine to normal operating temperature. |
| Engine emits white exhaust smoke | Defective thermostat | Remove and check thermostat. |
| Engine emits white exhaust smoke | Engine out of time | See your local dealer. |
| Engine emits white exhaust smoke | Defective injection nozzles | See your local dealer. |
Fault codes and symptom→remedy steps extracted from this model’s service/owner documentation; verify against the official manual before servicing.
Documented causes: Engine overload; Intake air restriction; Clogged primary fuel filter element; Clogged secondary fuel filter element. See the table for the matching fixes.
Documented causes: Improper starting procedure; No fuel; Low battery output; Excessive resistance in starting circuit. See the table for the matching fixes.
Documented causes: Improper type of fuel; Clogged or dirty air cleaner; Engine overload; Improper valve clearance. See the table for the matching fixes.