Electronic Modular Control Panel II (EMCP II) For MUI Engines Caterpillar

Illustration 1	g00595836
Schematic For Pressure Sensor (Engine Oil)

To find the cause of a low oil pressure shutdown, perform this procedure.

1. Check for a diagnostic fault.

   1. Check for a CID 100 (oil pressure sensor) or a CID 269 (sensor power supply) that is active. See Testing And Adjusting, "Troubleshooting Diagnostic Codes".

      Expected Result: CID 100 or CID 269 should not be showing.

      Results:

      • OK - Proceed to 2.

      • Not OK - Correct the active CID 100 or CID 269 prior to proceeding with this procedure. See Testing And Adjusting, "Troubleshooting Diagnostic Codes". STOP.

2. Check obvious causes.

   1. Check for low oil pressure.

   2. Check oil level.

   3. Check for oil leaks.

   4. Check for other obvious causes of low oil pressure.

      Expected Result: No obvious cause should exist.

      Results:

      • OK - Proceed to 3.

      • Not OK - An obvious cause does exist. Correct the fault. Refer to the Engine Service Manual. STOP.

3. Check setpoints.

   This step checks the setpoints P12 (oil step speed), P13 (low oil pressure at rated speed) and P14 (low oil pressure at idle speed).

   1. View the setpoints and note the setpoints P12, P13, and P14. See Systems Operation, "Engine/Generator Setpoint Viewing OP2".

   2. Compare the setpoints that are viewed with the specified setpoints of the particular generator set.

      Expected Result: The setpoint value that is viewed and the setpoint value that is specified should agree.

      Results:

      • OK - Proceed to 4.

      • Not OK - The setpoints do not agree. Reprogram setpoints P12, P13 and P14. See Systems Operation, "Engine/Generator Programming OP5". STOP.

4. Check the function of low oil pressure.

   1. Turn the ECS to the OFF/RESET position and then turn the ECS to the START position.

   2. Allow oil pressure to stabilize.

   3. When the engine is at idle speed, compare the actual pressure that is showing on the lower display with setpoint P14. The actual pressure that is showing should be greater than setpoint P14.

   4. When the engine is at rated speed, compare the actual pressure that is showing on the lower display with setpoint P13. The actual pressure that is showing should be greater than setpoint P13.

      Expected Result: The actual pressure at idle speed and at rated speed should be greater than the setpoint value. These actual pressures should not cause a low oil pressure shutdown.

      Results:

      • OK - Both actual pressures are greater than the corresponding setpoint value and the low oil pressure indicator does not FLASH. The problem is not present now. The problem may be intermittent. Check the harness and all the electrical connections of the oil pressure circuit. See Testing And Adjusting, "Electrical Connector - Inspect". STOP.

      • OK - Both actual pressures are greater than the corresponding setpoint value and the low oil pressure indicator remains FLASHING. Therefore, the GSC is faulty. Replace the GSC. See Testing And Adjusting, "EMCP Electronic Control (Generator Set) - Replace". STOP.

      • Not OK - Actual pressure showing is less than the setpoint for rated speed or idle speed. The pressures are correct for a low oil pressure shutdown. Therefore, the engine should shut down and the low oil pressure indicator should FLASH. The GSC is operating properly. Refer to the Engine Service Manual in order to find the cause of low oil pressure. STOP.

      Note: Check the accuracy of the pressure that is shown on the lower display of the GSC. Install an accurate engine oil pressure gauge as close as possible to the engine oil pressure sensor for the EMCP II.