KIT-ENGINE OVERHAUL 3599753 - Caterpillar

Illustration 1 g02773641
Connections of the Hoe Right Joystick Thumbwheel position sensor
This diagnostic code is associated with the Hoe Right Joystick Thumbwheel position sensor. The position sensor provides a PWM input signal to the Machine ECM. The position sensor is embedded in the handle of the joystick. The FMI 08 diagnostic code is activated when the ECM detects an input signal of abnormal frequency or abnormal pulse width.The sensor is a PWM sensor that operates at a frequency of approximately 500 100 Hz. The duty cycle of the PWM signal that is supplied to the ECM is measured in small increments. The changes in the duty cycle of the sensor cannot be measured with a digital multimeter.The following conditions could cause this diagnostic code to be activated:
The sensor has failed.
There are intermittent connections or poor connections in the signal circuit.
The ECM has failed. This condition is unlikely.Note: Before performing this procedure, check for an active CID 0041 diagnostic code for the 8V sensor power supply of the Machine ECM. Correct any problem with the 8V power supply before performing this procedure.Before performing this procedure, inspect the harness connectors that are involved in the circuit. Poor connections are often 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: The following test procedure may create other diagnostic codes. Clear the diagnostic codes when the original diagnostic code has been corrected.Test Step 1. CHECK THE SENSOR
Turn the key start switch and the disconnect switch to the ON position.
Disconnect the machine harness connector from the position sensor. Observe the status of the active CID 2531 FMI 08 diagnostic code.
Observe the status of the active diagnostic code for the position sensor. Expected Result:The status of the CID 2531 FMI 08 diagnostic code did not change when the position sensor was disconnected. A CID 2531 FMI 03 diagnostic code has not been activated by the ECM. The CID 2531 FMI 08 diagnostic code remains active when the sensor disconnected.Results:
OK - The CID 2531 FMI 08 diagnostic code remains active when the sensor is disconnected. The sensor is not the cause of the problem. Proceed to Test Step 2.
NOT OK - The status of the CID 2531 FMI 08 diagnostic code is no longer active when the sensor was disconnected. The CID 2531 FMI 03 diagnostic code is activated by the ECM when the position sensor is disconnected. The machine harness and ECM are operating correctly.Repair: The operation of the position sensor is the cause of the problem. Replace the joystick. After replacement of the joystick, verify that the operation is correct before operating the machine.STOPTest Step 2. CHECK FOR AN OPEN IN THE SIGNAL CIRCUIT
Turn the key start switch and disconnect switch to the OFF position.
Disconnect the machine harness connector from the position sensor.
At the machine harness connector for