OPTION AR-REGIONAL 3844103 - Caterpillar

Illustration 1 g01501513
Connections of blade right constant downforce control position sensor This diagnostic code is associated with the blade right constant downforce control position sensor. The FMI 04 is activated when the Implement ECM detects a below normal voltage or a below normal duty cycle of the signal circuit of the position sensor. The position sensor is connected to the right downforce operator control dial. The position sensor will supply a PWM signal to the Implement ECM in order to indicate the position of the dial. The position sensor operates at a frequency of approximately 500 hertz. The PWM sensor sends a PWM input signal to the ECM. The variations in the duty cycle of the signal follows:
When the blade downforce dial is moved to the full clockwise position, the duty cycle of the PWM signal is approximately 93%.
When the blade downforce dial is moved through a detent to the full counterclockwise position, the duty cycle of the PWM signal is approximately 10.6%.The following conditions could cause this diagnostic code to be activated:
The sensor has failed.
The signal circuit for the sensor is shorted to a ground source.
The ECM has failed. This is unlikely. 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. If a problem with a connection is found, correct the problem and verify that this diagnostic code is active before performing this procedure.Note: This procedure can cause new diagnostic codes to be activated. Clear the diagnostic codes, when the problem has been corrected.Test Step 1. CHECK THE SENSOR
Turn the disconnect switch to the ON position.
Turn the key start switch to the ON position.
While the status of the diagnostic code is observed, disconnect the machine harness connector from the blade right constant downforce control position sensor.Expected Result:The FMI 04 diagnostic code will remain active if the sensor is not the cause of the problem. The FMI 04 diagnostic code changes to an active FMI 03 diagnostic code when the sensor is disconnected from the machine harness. The sensor is internally shorted.Results:
OK - The FMI 04 diagnostic code remains active. The sensor has not failed. Proceed to Test Step 2.
NOT OK - The FMI 04 diagnostic code changes to an FMI 03 diagnostic code when the sensor is disconnected. The machine harness and the ECM are operating correctly.Repair: The blade right constant downforce control position sensor has failed. Replace the sensor. After replacement of the sensor, verify that the operation of the new sensor is correct before operating the machine.STOPTest Step 2. CHECK THE SENSOR CIRCUIT FOR A SHORT
The position sensor remains disconnected from the machine harness.
Turn the disconnect switch to the OFF position.
Turn the key start switch to the OFF position.
Disconnect the machine harness connectors J1 and J2 from the Implement ECM.
At the machine harness connector J2 for the ECM, perform the following:
Measure the