Use this procedure if an engine shutdown occurs and the low oil pressure fault indicator is flashing.
Test Step 1. Inspect Electrical Connectors and Wiring
- Turn the main disconnect switch to the OFF position.
- Thoroughly inspect all of the connectors that are associated with the circuit.
Expected Result:
All connectors, pins and sockets are completely coupled and/or inserted and the harness and wiring are free of corrosion, of abrasion and of pinch points.
Results:
- OK - The harness and connectors appear to be OK. Proceed to Test Step 2.
- Not OK - There is a problem with the connectors and/or wiring.
Repair: Repair the connectors or wiring and/or replace the connectors or wiring. Ensure that all of the seals are properly in place and ensure that the connectors are completely coupled.Verify that the repair eliminates the problem.
STOP
Test Step 2. Check the Status Control Module (SCM)
- Turn the main disconnect switch to the ON position.
- Turn the Engine Control Switch (ECS) to the OFF/RESET position.
Expected Result:
The fault indicator resets.
Results:
- OK - The fault indicator resets. Verify that there are no possible causes for low oil pressure. Proceed to Test Step 3.
- OK - The fault indicator does not reset.
Repair: Proceed to Troubleshooting, "Fault Indicator Does Not Reset".
STOP
Test Step 3. Check the Setpoints for Oil
- Turn the ECS to the START position.
- Start the engine. Run the engine normally.
Expected Result:
The engine starts. The engine runs normally.
Results:
- OK - The engine starts. The engine runs normally. The setpoints are correct. Proceed to Test Step 4.
- Not OK - The engine did not start and/or the engine did not run normally.
Repair: Reprogram the following setpoints: "Oil Step Speed", "Rated Speed Oil Pressure Shutdown" and "Idle Speed Oil Pressure Shutdown". Proceed to Testing and Adjusting, "Setpoint Programming".
STOP
Test Step 4. Verify the Oil Pressure
- Install a reliable oil pressure gauge. The 1U-5470 Engine Pressure Group has a gauge that measures the oil pressure in the engine. Refer to Special Instruction, SEHS8907 for more information on the 1U-5470 Engine Pressure Group. The information is included in the tool group.
- Start the engine.
- Compare the gauge pressure reading against the pressure reading displayed on the SCM at idle speed and at rated speed.
Note: If the oil pressure is low, immediately shut down the engine and troubleshoot the low pressure problem.
Expected Result:
The gauge pressure reading and the SCM display reading are the same.
Results:
- OK - The gauge pressure reading and the SCM display reading are the same. Proceed to Test Step 5.
- Not OK - The gauge pressure reading and the SCM display reading are not the same.
Repair: There may be a problem with the electrical connectors and/or wiring.If necessary, repair the connectors or wiring and/or replace the connectors or wiring.Troubleshoot the circuit for the oil pressure sensor. Troubleshoot the module for the pressure and temperature. Refer to Troubleshooting, "02 dIAG".
STOP
Test Step 5. Compare the Pressure Reading On the Gauge to the Programmed Setpoints
- If necessary, restart the engine.
- Compare the pressure reading on the gauge against the programmed setpoints at idle speed and at rated speed.
- Shut down the engine.
Expected Result:
The same pressure reading is displayed on the gauge. The same set points are programmed.
Results:
- OK - The same pressure reading is displayed on the gauge. The same setpoints are programmed.
Repair: There may be a problem with the electrical connectors and/or wiring.If necessary, repair the connectors or wiring and/or replace the connectors or wiring.Troubleshoot the circuit for the oil pressure sensor. Troubleshoot the module for the pressure and temperature.Refer to Troubleshooting, "02 dIAG".
STOP
- Not OK - The same pressure reading is not displayed on the gauge or the same set points are not programmed.
Repair: Reprogram the following setpoints for oil: "Oil Step Speed", "Rated Speed Oil Pressure Shutdown" and "Idle Speed Oil Pressure Shutdown". Proceed to Testing and Adjusting, "Setpoint Programming".
STOP