FLANGE-WHEEL 4826773 - Caterpillar

Illustration 1 g02705397
Schematic for the Steering Oil Temperature Sensor
This diagnostic code is recorded when the ECM reads the input signal from the Steering Oil Temperature Sensor and determines that the signal frequency or the signal pulse width is not within the expected range.The sensor is a PWM sensor that operates at a frequency of approximately 500Hz 200Hz. The sensor sends a PWM input signal to the ECM. The duty cycle of the signal will vary from 5% to 95%.If the PWM frequency is outside the 500Hz 200HZ operating range, an FMI 08 diagnostic code will be activated.The possible causes of this condition are listed below:
Intermittent connections or poor connections in the wire harness.
The sensor has failed.
The ECM has failed. ECM failure is unlikely.System Response:
The events related to this sensor signal will not work properly.
Steering filter bypass warnings may not activate.Note: This diagnostic code is caused by an intermittent condition. The diagnostic code is active and the diagnostic code is inactive over a period.Note: Ensure that there are no active CID 262 diagnostic codes for the 5 V sensor power supply before performing this procedure. Ensure that CID 0075 FMI 08 diagnostic code is active. This test procedure may cause other diagnostic codes. Clear these diagnostic codes when the original diagnostic code 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 for the sensor, use a 151-6320 Removal Tool to remove the signal wire C451-YL(Yellow)and the socket at contact 3 from the harness connector. The machine harness connector remains connected to the sensor.
At the back of the sensor connector, insert 7X-1710 Multimeter Probes along the ground contact 2 and the signal contact 3.
Turn the disconnect switch and the key start switch to the ON position.
Measure the frequency of the signal from the sensor.
Observe the measurement and wiggle the sensor connector. Gently pull on the wires and wiggle the wires.
Measure the duty cycle of the sensor at the connector pins between the contacts 2 and 3. Check that the sensor is within range according to the description at the beginning of this procedure.Expected Result:The frequency and 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. 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 sensor is not correct. Replace the sensor. After replacement, verify that the operation is correct before operating the