PLATE 1065814 - Caterpillar

Illustration 1 g02432336
Schematic of "Boom Cylinder Rod Pressure" sensorThis diagnostic code is associated with the "boom cylinder rod pressure" sensor. The FMI 03 diagnostic code indicates that the Machine ECM is detecting a voltage for the pressure sensor that is above normal. Conditions that can cause this diagnostic code to be activated are listed below:
There is a problem with the sensor power supply.
The signal circuit for the sensor has an open or a bad connection.
The signal circuit for the sensor is shorted to a voltage source.
The sensor has failed.
The Machine ECM has failed. This situation is unlikely.Note: When this diagnostic code is activated, verify that there are no other active diagnostic codes for the pressure sensor. All active diagnostic code for the pressure sensor must be cleared before proceeding with this procedure.Note: Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, that all connections are secure and that all connections are in good condition. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure. 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.Test Step 1. CHECK THE SENSOR POWER SUPPLY
Turn the key start switch and the disconnect switch to the ON position.
Disconnect the machine harness connector from the sensor.
At the machine harness connector for the sensor, measure the supply voltage between the contact of the power supply 1 (wire E774-GN) and the ground contact 2 (wire 998-BR).Expected Result:The measurement of the supply voltage is 8.0 0.3 VDC.Results:
OK - The voltage measurement is approximately 8.0 0.3 VDC. The power supply for the sensor is correct. Proceed to Test Step 2.
NOT OK - The voltage measurement is less than 8.0 0.3 VDC. The power supply for the sensor is not correct. Repair: Either the return circuit 998-BR or the supply circuit E774-GN has a bad connection or an open in the machine harness. Examine all of the connectors that are in the circuit. Ensure that the connections are clean, that the connections are secure and that the connections are in good condition. Refer to the CID 0262 diagnostic code procedure in this manual for troubleshooting of the power supply. Correct the problem with the ECM power supply. After the power supply is correct, verify that this diagnostic code is still active before proceeding with this procedure.STOPTest Step 2. CHECK FOR AN OPEN IN THE SENSOR CIRCUITThe machine harness connector remains disconnected from the sensor.
Turn the key start switch and the disconnect switch to the OFF position.
At the machine harness connector for the sensor, place a jumper wire between the return contact of the sensor 2 (wire 998-BR) and the signal contact 3 (wire M844-OR) .
Disconnect machine harness connectors