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| Illustration 1 | g02442696 |
| (1) Attachment two lever implement controls with auxiliary third function lever | |
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| Illustration 2 | g02652900 |
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Connections of the Auxiliary Third Lever Position Sensor | |
This diagnostic code is associated with the Auxiliary Third Lever Position Sensor. The position sensor is located in the implement control lever. The FMI 08 means that the ECM has determined that the signal frequency or the signal pulse width is not within the expected range.
The duty cycle of the PWM sensor input signal will change according to the amount of lever movement on the forward / rearward axis. Each position sensor signal operates at approximately 500 ± 100 Hz.
The lever position sensor is supplied system voltage through the right column, fuse F39 in the switched upper fuse panel (10A - circuit 146-GY). The sensor is supplied an ECM ground circuit (C214-BK) connection from the Implement ECM J1-70 contact.
This ground circuit is used for ECM location code ground connections and for ground supply connections. Most of the switches and sensors that are connected to the two ECMs also use this ground circuit.
The following table indicates the PWM duty cycles that the ECM will consider as acceptable in the indicated standard lever and auxiliary lever positions.
| Lever Position | Acceptable Sensor PWM Duty Cycle (Percent) |
| Full Forward | 7 to 14 |
| Centered | 50 ± 4 |
| Full Rearward | 85 to 93 |
The possible causes of this diagnostic code are listed below:
- The sensor has failed.
- Intermittent connections or poor connections
- The ECM has failed. This condition is unlikely.
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. Inspect the connections for the following:
- Connections are clean.
- Connections are secure.
- Connections are in good condition.
Note: 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 problem has been corrected.
Test Step 1. CHECK THE DUTY CYCLE AND THE SIGNAL FREQUENCY AT THE SENSOR
- Turn the key start switch and the disconnect switch to the OFF position.
- At the machine harness connector C4 for the implement control lever, use a 151-6320 Removal Tool to remove the signal wire H722-GN(Green) and the socket at contact 3 from the harness connector. The connector for the machine harness C4 remains connected to the connector of the implement control lever.
- At the back of the connector of the lever C4, insert 7X-1710 Multimeter Probes along the ground contact 2 and the signal contact at 3.
- Turn the disconnect switch and the key start switch to the ON position.
- With the lever in the stationary condition, measure the frequency of the signal from the sensor.
- Observe the measurement and wiggle the connector of the lever. Gently pull on the wires and wiggle the wires.
- Measure the duty cycle of the sensor at the connector pins of the lever between the contacts 2 and 3. Move the lever through the full range of the lever.
Expected Result:
The frequency of the lever sensor signal is 500 ± 100 Hz. The duty cycle of the signal is correct according to the description at the beginning of this procedure. The frequency and the duty cycle are stable during the manipulation of the harness connector and the wiring.
Results:
- OK - The signal frequency and the duty cycle of the sensor is correct. The sensor is not the cause of the problem. Reconnect the wire and the socket into the original locations in the ECM connector. Verify that all wires of the lever are secure in the connector. Proceed to Test Step 2.
- NOT OK - The signal frequency or the duty cycle of the sensor is not correct according to the description at the beginning of this procedure. The sensor has failed.
Repair: Perform this test step again in order to verify that the sensor signal is not correct.
The operation of the position sensor is not correct. Replace the implement control lever assembly. After replacement, verify that the operation is correct before operating the machine.
STOP
Test Step 2. CHECK FOR AN OPEN IN THE SENSOR CIRCUIT
- Turn the key start switch and the disconnect switch to the OFF position.
- Disconnect the machine harness connector C4 from the implement control lever. At machine harness connectors, place a jumper wire between the ground contact 2 (wire C214-BK(Black)) and the signal contact 3 (wire H722-GN(Green)).
- Disconnect machine harness connectors J1 and J2 from the Implement ECM.
- At the harness connectors for the ECM, measure the resistance from return contact J1-70 (wire C214-BK(Black)) to signal contact J2-26 (wire H722-GN(Green)).
- Observe the resistance measurement and wiggle the ECM connector and the sensor connector. Gently pull on the wires and wiggle the wires for both connectors.
Expected Result:
The resistance measurement is less than 5 ohms at all times during the manipulation of the wiring harness and connectors.
Results:
- OK - The resistance measurement is less than 5 ohms. The sensor signal circuit is not open in the machine harness. Proceed to Test Step 3.
- NOT OK - The resistance measurement for the signal circuit is greater than 5 ohms. There is an open or a poor connection in the circuit.
Repair: Check the signal circuit for opens or for a poor connection.
A resistance measurement that is greater than 5000 ohms would indicate an open in the circuit. A resistance that is greater than 5 ohms but less than 5000 ohms would indicate the following:
- A loose connection in the circuit
- A corroded connection in the circuit
- Connections are clean.
- Connections are secure.
- Connections are in good condition.
STOP
Test Step 3. CHECK THE STATUS OF THE DIAGNOSTIC CODE
- Perform the following:
- Visually inspect the harness connectors.
- Clean the contacts of the harness connectors.
- Visually inspect the insulation of the wires for damage that can be caused by excessive heat, battery acid, or chafing.
- Perform a
45 N (10 lb) pull test on each of the wires that are associated with the circuit. - Reconnect all harness connectors. Verify the following:
- The connectors are fully seated.
- The clips for each connector are fastened.
- Turn the disconnect switch and the key start switch to the ON position.
- Operate the machine.
- Check the status of the CID 0487 FMI 08.
Expected Result:
The CID 0487 FMI 08 is not active.
Results:
- OK - The CID 0487 FMI 08 is not active. The diagnostic code does not exist at this time. The initial diagnostic code was probably caused by a poor connection or a short at one of the connectors that was disconnected and reconnected. Resume normal operation
STOP
- NOT OK - The CID 0487 FMI 08 is active. The diagnostic code has not been corrected.
Repair: If available, perform a Wiggle Test on the machine wiring harness with the Caterpillar Electronic Technician (Cat ET) service tool. The Wiggle Test can detect the following in the machine wiring harness:
- Momentary shorts
- Intermittent shorts
- Opens
Exit this procedure and perform this procedure again. If the cause of the failure is not found, contact the Technical Communicator at your dealership for possible consultation with Caterpillar. This consultation may effect repair time.
If the ECM must be replaced, refer to Testing and Adjusting, "Electronic Control Module (ECM) - Replace".
STOP