416E, 420E and 430E Backhoe Loaders MID 039 - CID 2531 - FMI 04 Caterpillar

Conditions Which Generate This Code:

Illustration 1	g02115014
Schematic of the "Right-Hand Joystick Thumbwheel"

This diagnostic code is associated with the "Right-Hand Joystick" switch. The FMI 04 means that the ECM has determined that the voltage of the circuit for the switch is below normal.

The sensor operates at a frequency of approximately 500 hertz. The sensor has an operating duty cycle of 20% to 80%.

The possible causes of this diagnostic code are listed below:

• The signal circuit for the switch is shorted to ground.

• The sensor 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 2531 FMI 04 is active before performing this procedure.

Note: Use the 146-4080 Digital Multimeter for the measurements in this procedure.

Test Step 1. CHECK THE SENSOR SIGNAL CIRCUIT FOR AN OPEN

1. Turn the disconnect switch and the key start switch to the OFF position.

2. Access the "thumb wheel sensor ". The sensor is located under the "Right-Hand Joystick". Disconnect the sensor connector from the machine harness.

3. At the connector for the sensor, place a jumper wire between contact 1(wire X800-OR) and contact 3 (wire M965-GN).

4. Disconnect machine harness connector J1 from the ECM.

5. At the machine harness connector of the ECMJ1, measure the resistance between contact J1-44 (wire X800-ORL) and contact J2-41 (wire M965-GN).

Expected Result:

The resistance measurement is 5 ohms or less.

Results:

• OK - The resistance measurement is 5 ohms or less. The machine harness "connection"for the sensor signal is correct. Proceed to Test Step 2.

• NOT OK - The resistance measurement is greater than 5 ohms. There is a problem in the machine harness.

  Repair: There is an open circuit or a faulty connection in the sensor signal circuit for the thumb wheel sensor. The problem is in the sensor signal (wire X800-OR) or in the "sensor supply" (wire M965-GN) from contact J2-41 in the machine harness to the ECM. Repair the machine harness or replace the machine harness.

  STOP

Test Step 2. CHECK THE SENSOR SUPPLY CIRCUIT FOR AN OPEN

The machine wiring harness remains disconnected from the sensor.

The machine harness connector J1 remains disconnected from the ECM.

1. Turn the key start switch and the disconnect switch to the OFF position.

2. At the "three contact "connector for the sensor, place a jumper wire between contact 1 (wire X800-OR) and contact 2 (wire J764-BR).

3. At the machine harness connector for the ECM J1, measure the resistance between contact J2-44 (wire X800-OR) and contact J1-45 (wire J764-BR).

Expected Result:

The resistance measurement is 5 ohms or less.

Results:

• OK - The resistance measurement is 5 ohms or less. The machine harness "connection"for the "sensor supply"is correct. Proceed to Test Step 3.

• NOT OK - The resistance measurement is greater than 5 ohms. There is a problem in the machine harness.

  Repair: There is an open wire or a faulty connection in the "sensor ground " circuit for the thumb wheel sensor. The problem is in the ground circuit wire J764-BR. Repair the machine harness or replace the machine harness.

  STOP

Test Step 3. CHECK SENSOR SUPPLY VOLTAGE

The machine wiring harness remains disconnected from the sensor.

1. Connect machine harness J1 to the ECM.

2. Turn the key start switch and the disconnect switch to the ON position.

3. At the machine harness for the sensor, measure the "DC"voltage between contact 1 (wire X800-OR) and contact 2 (wire J764-BR).

Expected Result:

The voltage measurement should be between 7 to 11 DCV.

Results:

• OK - The voltage measurement is between 7 DCV to 11 DCV. The supply voltage is correct. The sensor is not working correctly.

  Repair: Replace the right hand joystick.

  STOP

• NOT OK - The voltage measurement is NOT between 7 DCV to 11 DCV. The ECM may have failed. Proceed to Test Step 4.

Test Step 4. CHECK IF THE DIAGNOSTIC CODE REMAINS.

1. Inspect the contacts of all of the machine harness connectors that are used in the "thumb wheel sensor" circuit. Clean the contacts of the connectors.

2. Reconnect all harness connectors.

3. Turn the disconnect switch and the key start switch to the ON position.

4. Operate the machine.

5. Check the status of the CID 2531 FMI 04 diagnostic code.

Expected Result:

The CID 2531 FMI 04 diagnostic code is still active.

Results:

• YES - The CID 2531 FMI 04 diagnostic code is still active. The diagnostic code has not been corrected. The ECM may have failed.

  Repair: It is unlikely that the ECM has failed. Exit this procedure and perform this procedure again. If the cause of the diagnostic code is not found, replace the ECM. See Testing and Adjusting, "Electronic Control Module (ECM) - Replace".

  STOP

• NO - The CID 2531 FMI 04 diagnostic code is not active. The diagnostic code does not exist at this time.

  Repair: The initial diagnostic code was probably caused by a poor electrical connection or a short at one of the harness connectors that was disconnected and reconnected. Resume normal machine operation.

  STOP