FILM-WARNING 3728052 - Caterpillar

Illustration 1 g01391318
Steer Sensor 1 connectionsThree steer position sensors are required for correct operation of the steering control. The steer position sensors are located in the Speed / Direction Handle. Each sensor provides an input signal to the Machine ECM that will indicate the position of the steering control handle. The FMI 04 diagnostic code is activated when the ECM detects that the signal voltage from the Steer Position Sensor 1 is below the acceptable range. The Steer Position Sensor 1 receives power from the Machine ECM 8 volt power supply circuit and the 8 volt return circuit.The position sensor is a PWM sensor that operates at a frequency of approximately 500 hertz. The position sensor sends a PWM input signal to the Machine ECM. The duty cycle of the signal will vary from approximately 10 percent when the steering control handle is at the full left position to approximately 90 percent when the steering control handle is at the full right position. When the steering control handle is at the center position, the duty cycle will be approximately 50%.The possible causes of this diagnostic code are listed:
The signal circuit is shorted to a ground source.
The sensor has failed.
The ECM has failed. This is unlikely. This procedure should not require entry into any enclosures that contain hazardous voltage components and should not require any hazardous voltage connections to be disconnected.When an area that contains hazardous voltage components must be entered for a service procedure, the "Safe Shutdown Procedure for Electric Drive Tractors" procedure must be performed before any enclosures that contain hazardous voltage components are opened or before any hazardous voltage connectors are disconnected. Refer to the Troubleshooting, "Electrical Maintenance Guidelines" section of this manual. Perform the "Safe Shutdown Procedure for Electric Drive Tractors" procedure before any of the hazardous voltage areas are opened or before hazardous voltage connectors are disconnected.Note: Poor connections can often be the cause of a problem in an electrical circuit. Verify that all connections in the circuit are clean, secure and 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 problem has been corrected.Test Step 1. CHECK THE SENSOR
Turn the disconnect switch and the key start switch to the ON position. DO NOT START THE ENGINE.
Disconnect the machine harness connector from the Speed / Direction Handle. Observe the status of the active CID 1471 FMI 04 diagnostic code.Expected Result:The status of the CID 1471 FMI 04 diagnostic code did not change when the harness connector was disconnected from the handle connector. A CID 1471 FMI 03 diagnostic code has NOT been activated by the Machine ECM. The CID 1471 FMI 04 diagnostic code remains active when the harness connector is disconnected.Results:
YES - The CID 1471 FMI 04 diagnostic code remains active when the harness connector