PISTON AS 3480313 - Caterpillar

Illustration 1 g01445619
Schematic of the Autolube Pressure SensorThis diagnostic code is associated with the autolube pressure sensor. The FMI 03 means that the ECM has determined that the voltage of the circuit for the sensor is above normal. The possible causes of this diagnostic code are listed below:
The signal circuit for the sensor is open.
The signal circuit for the sensor is shorted to the +battery circuit.
The sensor has failed.
The power circuit or the ground circuit has failed.
The ECM has failed. This is unlikely.Note: The following test procedure may create other diagnostic codes. Ignore these created diagnostic codes and clear the diagnostic codes when the original diagnostic code has been corrected. Ensure that the diagnostic code of CID 0379 FMI 03 is active before performing this procedure.Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.Test Step 1. CHECK FOR POWER AT THE SENSOR.
Do not disconnect the harness connector from the sensor.
At the back of the harness connector for the sensor, insert a 7X-1710 Multimeter Probe along contact A (wire C985-BU) for the voltage supply.
Turn the key start switch and the disconnect switch to the ON position.
Measure the voltage from contact A (wire C985-BU) to contact B (wire 298-BK).Expected Result:The voltage is 8 DCV.Results:
OK - The voltage is 8 DCV. Proceed to Test Step 3.
NOT OK - The voltage is not 8 DCV. The circuit is open. Repair: Repair the machine harness or replace the machine harness.STOPTest Step 2. CHECK THE SIGNAL CIRCUIT OF THE SENSOR.
Turn the key start switch and the disconnect switch to the OFF position.
At the back of the harness connector for the sensor, remove the 7X-1710 Multimeter Probe from contact A and insert the probe along the signal wire (contact C).
At the back of the harness connector for the sensor, insert the 7X-1710 Multimeter Probe along the ground wire (contact B).
Turn the disconnect switch and the key start switch to the ON position.
Monitor the signal of the sensor with the 146-4080 Digital Multimeter .
Without disconnecting the sensor or the hardware that is associated with the sensor from the machine, take the sensor through the full operating range of the sensor.Expected Result:The sensor's signal