KIT-PISTON 5081902 - Caterpillar

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 in order to perform this procedure.
Carefully install the spoons (multimeter probes) into the terminal locations for the sensor supply and the analog return on the sensor side of the connector for the suspect sensor.
While you observe the voltage reading on the multimeter, wiggle the wires and pull on the wires for the sensor supply and the analog return at the ECM connector. The voltage reading will not vary more than 0.5 volts 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 volts during either test.Results:
OK - The voltage reading did not vary more than 0.5 volts.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 volts 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 J1/P1 ECM connector.
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 of each of the jumper wires.
Remove the wires from terminal locations P1-2 (sensor supply) and P1-3 (analog return). Install a jumper wire into each of these terminal locations.
Connect the J1/P1 ECM connector.
Restore the electrical power to the engine. Set the engine control switch to the STOP position.
Measure the voltage between the jumper wire in P1-2 (sensor supply) and P1-3 (analog return).
Remove the electrical power from the engine. Set the engine control switch to the OFF/RESET position.
Restore the wiring to the original configuration. If the supply voltage between the jumper wires at the ECM is between 4.5 VDC and 5.5 VDC, the ECM is OK. There