Case IH 19042 (F-4360-02) – Engine Control Unit (ECU): Downstream SCR temperature sensor comparison to a calculated temperature value failure.

The Engine Control Unit (ECU) calculates an expected temperature model for the exhaust gas exiting the SCR chamber. This fault is triggered when the actual temperature reading from the downstream SCR temperature sensor deviates significantly from the ECU's calculated value, indicating sensor drift, failure, or an exhaust anomaly like a severe leak. This will typically trigger an engine derate or inducement mode.

• VESTRUM CVX
• 240 Series Axial-Flow Combines
• CR/CX Series Combines
• Puma Series (140, 150, 165, 185, 200, 220)
• Maxxum Series (115, 125, 135, 145, 150)
• Farmall Series (90C, 100C, 110C, 120C, 110U, 120U)
• Austoft 9900 Sugarcane Harvesters

1. 1

   Perform a cold start signal drift check using a diagnostic tool to monitor all exhaust temperature sensors before starting a cold engine; they should read within a few degrees of ambient temperature.

2. 2

   Inspect the downstream SCR temperature sensor pigtail and the main engine harness connector for melted wires, chafing, pushed-out pins, or corrosion (sensor operates on a 5V reference on Pin 1 and common ground on Pin 2).

3. 3

   Check for exhaust leaks by inspecting the exhaust piping and clamps between the SCR catalyst and the downstream sensor.

1. 1

   Cool Down

   Ensure the machine has been turned off and the exhaust aftertreatment system has completely cooled to prevent severe burns.

2. 2

   Locate the Sensor

   Locate the downstream SCR temperature sensor. It is threaded into the exhaust pipe directly after the SCR catalyst chamber.

3. 3

   Disconnect

   Unplug the sensor's electrical connector from the engine harness.

4. 4

   Remove the Sensor

   Using a line wrench or specialized sensor socket, carefully unthread the sensor from the exhaust pipe. If it is seized, apply penetrating oil and allow it to soak to prevent stripping the exhaust bung threads.

5. 5

   Install the New Sensor

   Apply a small amount of high-temperature anti-seize to the threads of the new sensor (if not already pre-applied by the manufacturer). Thread it in by hand to prevent cross-threading, then tighten to the OEM torque specification.

6. 6

   Reconnect

   Plug the sensor back into the engine harness, ensuring the locking tab clicks into place. Secure the wire away from direct heat sources.

7. 7

   Clear Codes and Verify

   Connect the Case IH EST diagnostic tool. Clear the inactive fault codes.

8. 8

   Mandatory Inducement Reset

   Run the 'SCR Fault Repair Verification Test' via the diagnostic tool to prove to the ECU that the system is functioning correctly and to lift the engine derate.