TUBE AS 3156646 - Caterpillar

Illustration 1 g01007876
Schematic of the circuit of the engine coolant temperature sensorThis diagnostic code is recorded when the ECM reads the signal voltage of the Engine coolant temperature sensor and the voltage is too high. The operating range for the output voltage of the sensor is approximately 0 DCV to 5 DCV.The possible causes of this diagnostic code are listed here:
The sensor has failed.
The return circuit of the sensor is open in the machine harness.
The signal circuit in the machine harness is shorted to a source of positive voltage.
The signal circuit in the machine harness is open or the sensor is disconnected.
The ECM has failed. This is unlikely. System Response:The diagnostic code of CID 0110 FMI 03 will be logged in the internal memory of the ECM. When the diagnostic code occurs, the following responses will occur.
The action alarm will sound.
The engine coolant gauge will display the maximum temperature.Test Step 1. CHECK THE CONTROL AND THE HARNESS.
Turn the disconnect switch and the key start switch to the ON position.
Disconnect the machine harness connector from the engine coolant temperature sensor.
At the machine harness connector for the sensor, measure the voltage (DCV) between the signal contact 1 (wire 441-OR) and the return contact 2 (wire J764-BR). Expected Result:The voltage is between 0 and 5 DCV.Results:
OK - The voltage is between 0 and 5 DCV. The ECM and the harness are correct. Repair: Replace the sensor. Stop.
NOT OK - The voltage is not between 0 and 5 DCV. The ECM may have failed or the harness has failed. Proceed to Test Step 2.Test Step 2. CHECK THE RETURN CIRCUIT OF THE HARNESS.
The sensor remains disconnected.
Turn the disconnect switch (if equipped) and the key start switch to the OFF position.
Disconnect the J1 and J2 machine harness connectors from the ECM.
Measure the resistance of the return circuit between contact 2 (wire J764-BR) of the machine harness for the sensor and contact J1-45 of the machine harness for the ECM. Expected Result:The resistance is less than 5 ohms. Results:
OK - The resistance is less than 5 ohms. The harness resistance is correct. Proceed to Test Step 3.
NOT OK - The resistance is greater than 5 ohms. The ground circuit in the harness has failed. There is an open circuit between the ground contact and frame ground. Repair: Repair the machine harness or replace the machine harness. Stop.Test Step 3. CHECK FOR A SHORTED HARNESS
The sensor and the ECM remain disconnected from the machine harness.
The disconnect switch and the key start switch remain in the OFF position.
At the machine harness connector for the sensor, measure the resistance between the signal contact 1 (wire 441-OR) and all contacts that are used in the machine harness connector for the ECM. Expected Result:Each resistance measurement is greater than 5000 ohms. Results:
OK - Each resistance measurement is greater than 5000 ohms. The ECM has failed.Repair: It is unlikely that an ECM has failed. Exit this procedure. Perform this diagnostic code procedure again. If the failure is not found, replace the