The Electronic Control Module (ECM) detects all of the following conditions:
- The engine has been running for at least ten seconds. This ten second delay begins once the engine speed is within 50 rpm of low idle. Also, the ten second delay allows the engine to build up oil pressure after engine start-up.
- 100-03 Engine Oil Pressure open/short to +batt is not active.
- 100-04 Engine Oil Pressure short to ground is not active.
- Engine oil pressure is inside the area of low oil pressure for at least five seconds. Refer to Illustration 1.
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| Illustration 1 | g01054359 |
Low oil pressure | |
System Response:
The ECM will log the warning. The ECM will transmit a warning to the display in the cab. The ECM will reset the warning when the oil pressure rises above the low pressure region in Illustration 1.
- Low power
- There may be a problem with the engine lubrication system.
- There may be a problem with the engine oil pressure sensor.
Test Step 1. Check the Engine Oil Level
- Check the engine oil level.
Expected Result:
The engine oil level is OK.
Results:
- OK - The engine oil level is OK. Proceed to Test Step 2.
- Not OK - The engine oil level is low.
Repair: Add engine oil to the proper level.
STOP
Test Step 2. Verify Proper Sensor Installation
- Check the installation of the engine oil pressure sensor.
- Check the wiring of the engine oil pressure sensor. Refer to the Electrical Schematic for the proper wiring. Ensure that all of the wires and connectors are properly connected.
Expected Result:
The sensor is properly installed and the wiring is correct.
Results:
- OK - The sensor is properly installed. Proceed to Test Step 3.
- Not OK - The sensor is not installed properly.
Repair: Install the engine oil pressure sensor properly. Repair the wiring and/or the connectors to the sensor.Verify that the repair eliminates the problem.
STOP
Test Step 3. Check for Active Diagnostic Codes
- Connect the Caterpillar Electronic Technician (Cat ET) to the data link connector.
- Check for active diagnostic codes that are related to the atmospheric pressure sensor and/or the turbocharger outlet pressure sensor.
Expected Result:
There are no diagnostic codes that are related to the atmospheric pressure sensor and/or the turbocharger outlet pressure sensor.
Results:
- OK - There are no diagnostic codes. Proceed to Test Step 4.
- Not OK - There is a diagnostic code that is related to the atmospheric pressure sensor and/or the turbocharger outlet pressure sensor.
Repair: Troubleshoot the diagnostic code before continuing with this procedure.
STOP
Test Step 4. Check the Supply Voltage to the Engine Oil Pressure Sensor
- Disconnect the engine oil pressure sensor.
- Turn the keyswitch to the ON position.
- Measure the voltage between terminal A (Engine Pressure Sensor +5V) and terminal B (Engine Pressure Sensor Common) of the connector for the engine oil pressure sensor on the engine harness.
Expected Result:
The voltage is 5.0 ± 0.16 VDC.
Results:
- OK - The voltage is within the range.
Repair: Temporarily connect a new engine oil pressure sensor.If the new sensor fixes the problem, reconnect the suspect sensor.If the problem returns, permanently replace the sensor.Verify that the repair eliminates the problem.
STOP
- Not OK - There is a problem with the 5 volt supply.
Repair: Check the sensor connector for corrosion and moisture.Check the 5 volt supply wire. Verify that the wire is not cut and that the wire is completely inserted into the connector for the engine oil pressure sensor on the engine harness.Verify that the repair eliminates the problem.
STOP