0446077 JOHNSON NUT, Oil sump to exhaust housing

Illustration 1 g01159952
Schematic for the engine pressure sensorsTest Step 1. Inspect the Electrical Connectors and the Wiring
Turn the keyswitch to the OFF position.
Illustration 2 g01159822
C11 pressure sensors (1) Boost pressure sensor (2) J2/P2 ECM connector (3) Atmospheric pressure sensor (4) Engine oil pressure sensor (5) Fuel pressure sensor
Illustration 3 g01159845
C15 pressure sensors (1) Boost pressure sensor (2) J2/P2 ECM connector (3) Atmospheric pressure sensor (4) Engine oil pressure sensor (5) Fuel pressure sensor
Thoroughly inspect ECM connector (2). Also, thoroughly inspect each of the connectors for sensors (1), (3), (4), and (5) .Refer to Troubleshooting, "Electrical Connectors - Inspect" for details.
Illustration 4 g01024457
P2 ECM connector (P2-15) Boost pressure sensor (P2-17) Sensor return (P2-28) Engine oil pressure sensor (P2-40) Fuel pressure sensor (P2-57) Atmospheric pressure sensor (P2-72) +5 V supply
Illustration 5 g01159881
Pressure sensor connector (typical example) (A) +5 V supply (B) Sensor return (C) Signal
Perform a 45 N (10 lb) pull test on each of the wires in the ECM connectors that are associated with the circuit. Also perform the pull test on all pressure sensor connectors that are in the circuit.
Check the allen head screw on each of the ECM connectors for the proper torque. Refer to Troubleshooting, "Electrical Connectors - Inspect" for the correct torque value.
Check the harness and wiring for abrasions and for pinch points from the sensors back to the ECM.Expected Result:All connectors, pins, and sockets are completely coupled and/or inserted. 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 in 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.STOPTest Step 2. Check the Supply Voltage at the Sensor Connector
Turn the keyswitch to the OFF position.
Disconnect all of the following pressure sensors at the sensor connector:
Fuel pressure sensor
Engine oil pressure sensor
Boost pressure sensor
Atmospheric pressure sensor
Turn the keyswitch to the ON position.Note: The original diagnostic code may go away. An open circuit diagnostic code for the sensor supply may become active when all of the sensors are disconnected. Ignore the active codes at this time and continue with this test step.
Measure the voltage between terminal A (5 V supply) and terminal B (sensor return) at the sensor connectors.
Turn the keyswitch to the OFF position.
Reconnect all sensors.Expected Result:The voltage is 5.0 0.2 VDC.Results:
OK - The voltage is 5.0 0.2 VDC. The voltage is correct. Proceed to Test Step 3.
Not OK - The voltage is not 5.0 0.2 VDC.Repair: The voltage is incorrect. Perform the diagnostic functional test Troubleshooting, "5 Volt Engine Pressure Sensor Supply Circuit - Test".STOPTest Step 3. Check for Active Diagnostic Codes
Connect Caterpillar Electronic Technician (ET) to the service tool connector.
Turn the keyswitch to the ON position.
Monitor the active diagnostic code screen on Cat ET. Check and record any active diagnostic codes.Note: Wait at least 15 seconds in order for the diagnostic codes to become active.
Determine if the problem is related to a 03 diagnostic code or a 04 diagnostic code.Expected Result:No diagnostic codes are active.Results:
OK - No diagnostic codes are active.Repair: The problem may have been related to a faulty connection in the harness. Carefully reinspect the connectors and wiring. Refer to Troubleshooting, "Electrical Connectors - Inspect".STOP
Not OK - A 04 diagnostic code is active at this time. Proceed to Test Step 4.
Not OK - A 03 diagnostic code is active at this time. Proceed to Test Step 5.Test Step 4. Disconnect the Suspect Sensor and Check for an Open Circuit
Turn the keyswitch to the OFF position.
Disconnect the sensor connector of the suspect sensor with the active 04 diagnostic code.
Turn the keyswitch to the ON position. Wait at least 15 seconds for activation of the diagnostic codes.
Use Cat ET to