- Starting aids
- Active engine derates
- J1939 Data Link
- Turbocharger outlet pressure sensor (intake manifold air), Rated fuel position and/or FRC fuel position
- Fuel supply
- Air inlet and exhaust system
- Accessory equipment
Make sure that the air inlet heater is programmed to the On position. For additional information on the Air Inlet Heater, refer to Troubleshooting, "Air Inlet Heater Circuit - Test".
If an active derate occurs, the warning lamp will flash. "Engine Derate" will appear in the first engine status box on the status screen for the Caterpillar Electronic Technician (Cat ET). Verify that the set points for "Derate" that are in the Programmable Monitoring System have been programmed to the values that are correct.
The signal from the throttle switch is carried on the J1939 Data Link. If the data link is not working properly, refer to Troubleshooting, "CAN Data Link Circuit - Test".
- Monitor the status "Fuel Position" and "Rated Fuel Limit" on Cat ET. If "Fuel Position" does not equal "Rated Fuel Limit" then check air inlet manifold pressure.
- Verify that there are no active diagnostic codes that are associated with the Turbocharger Outlet Pressure Sensor (intake manifold air) or the Atmospheric Pressure Sensor.
- Monitor turbocharger outlet pressure on the second Cat ET status screen and Atmospheric Pressure for normal operation.
Note: Atmospheric Pressure is not a default parameter on an Cat ET status screen. A new parameter screen must be set up in order to monitor the Atmospheric Pressure sensor.
- Check the fuel lines for the following problems: restrictions, collapsed lines and pinched lines. If problems are found with the fuel lines, repair the lines and/or replace the lines.
- Check the fuel tank for foreign objects which may block the fuel supply.
- Check for air in the low pressure fuel supply system if any of the following procedures have been performed:
- Replacement of the fuel filters
- Service on the low pressure fuel supply circuit
- Replacement of unit injectors
- Replacement of the fuel filters
- Purge air from the low pressure fuel supply circuit. Refer to Operation and Maintenance Manual, "Fuel System - Prime" for the correct procedure.
Note: A sight glass in the low pressure supply line is helpful in diagnosing air in the fuel.
- Check fuel quality. In temperatures below 0 °C (32 °F), check for solidified fuel (wax). Refer to Special Instruction, SEBD0717, "Diesel Fuels And Your Engine".
- Check the fuel pressure during engine cranking. Check the fuel pressure on the outlet side of the fuel filter. Refer to Specifications for correct pressure values. If the fuel pressure is low, replace the fuel filters. If the fuel pressure is still low, check the following items: fuel transfer pump, fuel transfer pump coupling and fuel pressure regulating valve.
- Clean plugged air filters or replace plugged air filters. Refer to the Operation and Maintenance Manual.
- Check the air inlet and exhaust system for restrictions and/or leaks. Refer to Testing and Adjusting, "Air Inlet and Exhaust System".
Check all accessory equipment for problems that may create excessive load on the engine. Repair any damaged components or replace any damaged components.