LINK 1523895 - Caterpillar

System Operation Description:Note: The electronic control module is connected.
Table 1
Sensor Voltage Specifications
Sensor Voltage Test
238-0112 Temperature Sensor
Temperature Resistance
(OHMS) Signal Voltage(1)
−40° C (−40° F) 33650.2 OHMS .9854 V
0° C (32° F) 3268.3 OHMS .8675 V
40° C (104° F) 532.3 OHMS .5161 V
80° C (176° F) 125.7 OHMS .2012 V
120° C (248° F) 39 OHMS .0725 V
150° C (302° F) 18.6 OHMS .0359 V
(1) The voltages that are listed in this table are guidelines for troubleshooting. The values should not be considered to be exact. The tolerance for these measurements is 10 percent. The proper operation of the sensor is more important. The output voltage of the sensor should change smoothly when the temperature changes. Locate the suspect sensor. Identify the sensor wires and connector contacts. See Diagnostic Function, "Pulse Width Modulated (PWM) Sensor - Test". DO NOT DISCONNECT ANY HARNESS CONNECTORS AT THIS TIME. Turn the key start switch to the ON position. DO NOT START THE ENGINE. Test Step 1. CHECK THE SENSOR POWER.
Identify the supply circuit and the ground circuit at the connector of the sensor.
Insert the 7X-1710 Cable Probes into the back of the connector of the sensor. Place the leads of the probe along side of the wires of the supply circuit and wires of the ground circuit.
Measure the system voltage. Expected Result:The voltage that is measured is between 7.5 and 8.5 DCV.Results:
YES - The voltage is between 7.5 and 8.5 DCV. The system voltage is present. Proceed to test step 2.
NO - The voltage is not between 7.5 and 8.5 DCV. There is an open circuit. Trace the supply circuit and the ground circuit in the machine harness.Repair: Repair the machine harness or replace the machine harness.STOPTest Step 2. CHECK THE SIGNAL VOLTAGE.
At the sensor connector, identify the signal and ground circuits.
Push the 7X-1710 Cable Probes in the back of the sensor connector along side of the signal and the ground circuit wires.
Measure the signal voltage and record the signal voltage. Note: If a precise signal voltage is necessary, use the specifications that are listed in the provided tables. Expected Result:The measured signal voltage is approximately between 1.0 and 7.0 DCV. The signal voltage is between 1.0 and 9.0 DCV with the 3E-5370 Temperature Sensor Group. Results:
FROM 1.0 TO 7.0 (9.0) DCV - The voltage is between 1.0 and 7.0 DCV (9.0 DCV for 3E-5370 Temperature Sensor Group). The signal voltage at the sensor is correct.Repair: The harness and the main display module are working properly. The voltage that is measured is correct. The sensor has failed. Replace the sensor.Proceed to test step 3.
GREATER THAN 7.0 (9.0) - The voltage is NOT between 1.0 and 7.0 DCV. (The Voltage is approximately 9.0 DCV for the 3E-5370 Temperature Sensor Group.) The signal voltage is not correct. The signal circuit of the machine harness is shorted to the +battery circuit.Repair: Repair the machine harness or replace the machine harness. Repeat this test step in order to verify that the problem has been