46 RENR5042-02 Troubleshooting Section Recommended Actions Note: A sight glass in the low pressure supply line is helpful in diagnosing air in the fuel. Refer to Systems Operation/Testing and Adjusting, “Fuel System” for more information. Diagnostic Codes and Event Codes Certain diagnostic codes and/or event codes may cause poor performance. Connect the Caterpillar Electronic Technician (ET) and check for active codes and logged codes. Troubleshoot any codes that are present before continuing with this procedure. NOTICE Do not crank the engine continuously for more than 30 seconds. Allow the starting motor to cool for two minutes before cranking the engine again. Throttle Signal 4.
Purge air from the low pressure fuel supply circuit. Refer to Operation and Maintenance Manual, “Fuel System - Prime” for the correct procedure. Connect Cat ET to the service tool connector. View the status for the throttle position on the status screen. Operate the throttle from the low idle position to the high idle position. The status should be 0 percent at low idle and the status should be 100 percent at high idle. Refer to Troubleshooting, “Throttle Position Sensor - Calibrate” if either value is incorrect. 5. Cold weather adversely affects the characteristics of the fuel.
Refer to the Operation and Maintenance Manual for information on improving the characteristics of the fuel during cold weather operation. 6. Check the fuel pressure after the fuel filter while the engine is being cranked. Refer to Systems Operation/Testing and Adjusting, “Fuel System Pressure - Test” for the 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. Refer to Systems Operation/Testing and Adjusting, “Fuel System” for additional information.
Diagnostic codes that are related to the J1939 data link will prevent correct operation of the throttle if the throttle position is transmitted over the data link. If there is a problem with the data link, the engine will remain at low idle until the data link is repaired. Electrical Connectors 1. Inspect the battery wires from the Electronic Control Module (ECM) back to the battery compartment. Refer to the Electrical System Schematic. Inspect the wires and the power relay. Check the power and ground connections to the ECM. Refer to the diagnostic functional test Troubleshooting, “Electrical Power Supply Circuit - Test” for more information. i02171503 Low Engine Oil Pressure SMCS Code:
1348-035-LP Fuel Supply NOTICE Do not operate the engine with low oil pressure. Engine damage will result. If measured oil pressure is low, discontinue engine operation until the problem is corrected. 1. 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. 2. Check the fuel tank for foreign objects which may block the fuel supply. Refer to Systems Operation/Testing and Adjusting, “Lubrication System” for information on engine oil pressure. 3. Check for air in the low pressure fuel supply system if any of the following procedures have been performed:
i02290611 Low Power/Poor or No Response to Throttle Replacement of the fuel filters Service on the low pressure fuel supply circuit SMCS Code: 1000-035 Replacement of unit injectors Probable Causes Diagnostic codes