STOP 9T3980 - Caterpillar

Conditions Which Generate This Code:
Illustration 1 g01248848
Schematic of the Transmission Oil Temperature SensorThis diagnostic trouble code is associated with the transmission oil temperature sensor. The FMI 01 means that the ECU has determined that the signal of the sensor is below the normal range. The possible causes of this failure are listed below:
The position sensor has failed.
The signal circuit of the sensor is shorted to the ground.
The sensor needs to be calibrated.
The ECU has failed. This is unlikely.Note: The following test procedure may create other diagnostic trouble codes. Ignore these created diagnostic trouble codes and clear the diagnostic trouble codes when the original diagnostic trouble code has been corrected.Note: Use a digital multimeter for the measurements in this procedure.Test Step 1. INSPECT THE SENSOR
Perform a visual inspection of the sensor, the wiring for the sensor and the hardware that is associated with the sensor.Expected Result:There is no apparent damage to the sensor, the wiring for the sensor or the hardware that is associated with the sensor.Results:
OK - There is no apparent damage to the sensor, the wiring for the sensor or the hardware that is associated with the sensor. Proceed to Test Step 2.
NOT OK - There is apparent damage to the sensor, the wiring for the sensor or the hardware that is associated with the sensor. Repair: Replace the damaged part. Proceed to Test Step 7.Test Step 2. CHECK FOR POWER AT THE SENSOR
Do not disconnect the harness connector from the sensor.
At the back of the harness connector for the sensor, insert a multimeter probe along the voltage supply wire contact A.
Turn the key start switch and the disconnect switch to the ON position.
Measure the voltage from contact A to frame ground.Expected Result:The voltage is 8 volts.Results:
OK - The voltage is 8 volts. Proceed to Test Step 3.
NOT OK - The voltage is not 8 volts. The circuit is open. Repair: Repair the machine harness or replace the machine harness.STOPTest Step 3. CHECK FOR PROPER GROUND AT THE SENSOR
The machine harness remains connected to the sensor.
Turn the key start switch and the disconnect switch to the OFF position.
Remove the multimeter probe from the voltage supply wire contact A.
At the back of the harness connector for the sensor, insert a multimeter probe along the