NOZZLE GP-INJ 4499153 - Caterpillar

Multimeter Probe (BLACK) onto the test leads of a multimeter.Note: Ensure that the multimeter probes are in good repair. Bent probes may contact other terminals inside the connector.
Check for an intermittent problem at the ECM connector:Note: Do not disconnect any harness connectors to perform this procedure.
Carefully install the spoons (multimeter probes) into the terminal locations for the appropriate sensor supply and the analog return at the ECM connector.
While you observe the voltage reading on the multimeter, wiggle the wires and pull on the wires at the connector for the suspect sensor.The voltage reading will not vary more than 0.5 V for a solid electrical connection.
Remove the spoons (multimeter probes) from the connector.
Check for an intermittent problem at the connector for the suspect sensor:Note: Do not disconnect any harness connectors to perform this procedure.
Carefully install the spoons (multimeter probes) into the terminal locations for the sensor supply and the analog return. Install the spoons on the sensor side of the connector for the suspect sensor.
Perform a manual wiggle test on the circuit . While you observe the voltage reading on the multimeter, wiggle the wires for the supply and the return at the ECM connector.The voltage reading will not vary more than 0.5 V for a solid electrical connection.
Remove the spoons (multimeter probes) from the connector.
Remove the electrical power from the ECM.Expected Result:The voltage reading did not vary more than 0.5 V during either test.Results:
OK - The voltage reading did not vary more than 0.5 V.Repair: The connections are OK at the connectors. There does not appear to be an intermittent problem in the circuit at this time. Return the engine to service.STOP
Not OK - The voltage reading varied more than 0.5 V during the test.Repair: Disconnect the suspect connector and inspect the connector and the terminals for moisture, damage, and corrosion. Repair the connectors and/or the terminals. Return the engine to service.STOPTest Step 3. Check the Supply Voltage at the Sensor Connector
Disconnect the harness connector for the suspect sensor.
Measure the voltage between the terminals for the sensor supply and the analog return at the harness connector for the suspect sensor.Expected Result:The voltage is between 4.5 VDC and 5.5 VDC.Results:
OK - The voltage is between 4.5 VDC and 5.5 VDC. The supply voltage is reaching the sensor connector. Record the voltage measurement. If you are troubleshooting a -3 diagnostic code, proceed to Test Step 4. If you are troubleshooting a -4 diagnostic code, proceed to Test Step 7.
Not OK - The voltage is less than 4.5 VDC or the voltage is greater than 5.5 VDC.Repair: The supply voltage at the sensor connector is incorrect. There appears to be a problem in the wiring harness or in a connector. There may be a problem with the power supply at the ECM. Perform the following procedure:
Disconnect the appropriate ECM connector that is for the affected sensor supply.
Fabricate two jumper wires that are long enough to be used to create test circuits at the ECM connector. Crimp connector sockets to one end