Case IH 19481 (F-519550-02) – Engine ECU (Engine Control Unit): Fault check for cold start condition of exhaust-gas temperature sensor 3 only.

Indicates a signal drift or plausibility error in Exhaust Gas Temperature (EGT) Sensor 3 (located downstream of the SCR catalyst). The system runs a model-based plausibility check during a cold start, and flags the sensor if it reports a temperature significantly different from ambient air, coolant, or other exhaust temperature sensors.

• VESTRUM CVX
• Case IH Farmall Series (40, 45, 50, 100C, 105U, 110A, 115C, 120U)
• Case IH Maxxum Series (120, 125, 130, 140)
• Case IH Puma Series (140)
• Case IH Magnum Series (225)
• Case IH Combines (5130, 5140, 7130, 7240, 9230)
• Case CE skid steers and wheel loaders

1. 1

   Perform a cold soak verification by allowing the machine to sit completely turned off for at least 6 hours to ensure a true cold engine state.

2. 2

   Connect the Electronic Service Tool (EST) and compare the temperature reading of EGT Sensor 3 against the Coolant Temperature Sensor, Ambient Air Temperature Sensor, and EGT Sensors 1 & 2. If EGT 3 is reading a drastically different value, the sensor has drifted and failed.

3. 3

   Inspect the wiring and connector for EGT Sensor 3 (TEMP IN B246 or B247) for corrosion, moisture intrusion, or wire chafing, which can artificially alter the resistance and cause a false temperature reading.

1. 1

   Power Down

   Turn off the machine and disconnect the negative battery cable to prevent electrical shorts.

2. 2

   Locate the Sensor

   Locate EGT Sensor 3, which is threaded into the exhaust pipe downstream of the SCR (Selective Catalytic Reduction) catalyst.

3. 3

   Remove the Sensor

   Disconnect the sensor's electrical connector. Carefully unscrew the sensor from the exhaust pipe. (Penetrating oil may be required if the sensor is seized due to exhaust heat).

4. 4

   Prepare the New Sensor

   Apply a high-temperature, non-silicone anti-seize compound (such as Loctite 8009) to the threads of the new sensor to prevent future seizing. Note: Do not get grease on the sensor probe itself.

5. 5

   Install the Sensor

   Thread the new sensor into the exhaust pipe and tighten it to the OEM specified torque (typically around 30-50 Nm depending on the specific exhaust pipe thread size).

6. 6

   Reconnect

   Plug the sensor connector back into the engine wiring harness. Reconnect the negative battery cable.

7. 7

   Clear Codes and Heal

   Connect the EST laptop, clear the inactive 19481 fault code, and run the SCR system 'healing procedure' or system test to verify the new sensor is reading correctly and to take the tractor out of derate/limp mode.