Case IH 19484 (F-519546-02) – Engine Control Unit (ECU) / Engine Control Module (ECM): Fault check for Model based plausibility check of fourth exhaust-gas temperature.

The engine control system is comparing the actual temperature reading from the 4th exhaust gas temperature (EGT) sensor against a calculated (model-based) temperature value. When the physical sensor's reading deviates too far from what the software model predicts it should be under current operating conditions, the system flags the sensor reading as "implausible" and logs this fault.

• VESTRUM CVX
• Case IH Farmall Series: 40, 45, 50 (with Cab and CVT Transmission), 100C, 105A/C/U, 110A/C/U, 115A/C/U, 120U
• Case IH Maxxum Series: 115, 120, 125, 130, 140, 145, 150
• Case IH Puma Series: 140 and up
• Case IH Combines / Harvesters: 5130, 5140, 7130, 7140, 7150, 7230, 7240, 7250, 9230
• Case N-Series TLBs (Tractor Loader Backhoes): Tier 4 Final models
• Optum Series Tractors
• Quantum Series Tractors
• Vestrum Series Tractors

1. 1

   Visually inspect the wiring harness and the 2-pin Bosch connector leading to the 4th EGT sensor for chafing, melting, corrosion, or loose connections

2. 2

   Inspect the exhaust piping and SCR/DPF housing near the sensor for exhaust leaks. A leak can alter the actual temperature reaching the sensor, causing a plausibility mismatch.

3. 3

   Remove the sensor and check for excessive soot buildup or physical damage to the probe

4. 4

   Ensure there are no active codes for ambient air temperature, DEF pressure, or upstream/downstream NOx sensors (e.g., 19454, 19455, 19496), as these can skew the ECU's model-based temperature calculations

1. 1

   Safety First

   Park the machine on a level surface, turn off the engine, and allow the exhaust system to cool completely. Exhaust components reach extremely high temperatures during operation and regeneration.

2. 2

   Locate the Sensor

   Locate the 4th exhaust gas temperature sensor on the aftertreatment/exhaust housing (typically threaded into the exhaust stream near the DPF/SCR assembly).

3. 3

   Disconnect Wiring

   Carefully unplug the 2-pin electrical connector. Be gentle to avoid damaging the main wiring harness.

4. 4

   Remove the Sensor

   Use a wrench (typically 17mm) to unthread the sensor from the exhaust housing. If it is stuck, apply penetrating oil and allow it to soak to prevent stripping the threads.

5. 5

   Prepare the New Sensor

   Apply a high-temperature anti-seize compound to the threads of the new sensor (avoid getting any on the sensor probe itself).

6. 6

   Install the New Sensor

   Thread the new sensor into the housing by hand to prevent cross-threading, then tighten to the OEM torque specification.

7. 7

   Reconnect

   Plug the 2-pin electrical connector back into the harness.

8. 8

   Clear Codes and Test

   Use a diagnostic tool to clear the 19484 fault code. Run the machine up to operating temperature or perform a manual regeneration to verify the sensor is reading correctly and the code does not return.