TRUNNION 0505631 - Caterpillar

Illustration 1 g02402856
Connections of the Right Joystick Left Right Position Sensor
This diagnostic code is associated with the Right Joystick Left Right Position Sensor. The position sensor is located in the right joystick. 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 position sensor is a PWM sensor that operates at a frequency of approximately 500 100 Hz. The position sensor sends a PWM input signal to the ECM. The duty cycle of the signal will vary from 7% to 93%. The variations in the duty cycle of the signal follow:
Table 1
Joystick Position Acceptable Sensor PWM Duty Cycle (Percent)
Full Forward / Full Right 7 to 14
Centered 45 to 55
Full Rearward / Full Left 85 to 93 The possible causes of this diagnostic code are listed:
The sensor has failed.
Intermittent connections or poor connections.
The ECM has failed. This condition is unlikely. Note: If a CID 1482 diagnostic code for the 10V power supply has been activated, investigate and fix the problem before proceeding with this procedure.Note: The correct operating temperature range for the sensor is −40 °C (−40.0 °F) to 75 °C (167.0 °F). When the environment of the cab is at extreme temperatures, an FMI 03 or an FMI 08 the diagnostic code becomes active. Standardize the environment of the cab, in order to keep the sensors operating in the acceptable temperature range. After standardizing the temperature to normal, verify that the CID 2477 FMI 08 diagnostic code is active before performing 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. 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 C2 for the right joystick, use a 151-6320 Removal Tool to remove the signal wire H711-GN(Green) and the socket at contact 3 from the harness connector. The connector for the machine harness C2 remains connected to the connector of the right joystick.
At the back of the connector of the joystick C2, 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 joystick in the stationary condition, measure the frequency of the signal from the sensor.
Observe the measurement and wiggle the connector of the joystick. Gently pull on the wires and wiggle the wires.
Measure the duty cycle of the sensor at the connector