Case IH 19052 (F-3223-06) – Engine Control Unit (ECU) / Engine Management System (EMS): Upstream NOx sensor internal failure (Heater Short Circuit Error)

The Engine Management System has detected a short circuit specifically within the internal heating element of the upstream Nitrogen Oxide (NOx) sensor.

• VESTRUM CVX
• 240 Series Axial-Flow Combines
• Axial-Flow 5130 Combines
• Austoft 9900 Sugarcane Harvesters
• Steiger 580 Tractors
• Farmall 40-45-50 Tractors (with CVT)
• Magnum series tractors
• Puma series tractors

1. 1

   Acknowledge symptoms: Check for DEF/AdBlue warning light, Stop Engine/Fault light, and engine torque limitation (derate).

2. 2

   Locate the upstream NOx sensor in the exhaust stream directly before the Diesel Oxidation Catalyst (DOC).

3. 3

   Inspect the wiring harness and the sensor connector (C186) for chafing, melting, or a physical short to ground.

1. 1

   Turn off the machine and ensure the exhaust system has cooled down.

   Specifically ensure the DOC area has cooled down to a safe temperature.

2. 2

   Locate the upstream NOx sensor.

   Located prior to the DOC.

3. 3

   Disconnect the sensor's wiring harness connector.

4. 4

   Verify the failure is internal to the sensor.

   If the wiring harness side shows no signs of a short circuit, the failure is internal to the sensor's heater element (as the code specifies).

5. 5

   Remove the defective upstream NOx sensor.

   Remove it from the exhaust pipe.

6. 6

   Install the new upstream NOx sensor.

   Torque to OEM specifications.

7. 7

   Reconnect the wiring harness.

8. 8

   Clear the fault code and verify the repair.

   Connect a diagnostic tool to clear the active 19052 (F-3223-06) / 256E fault code from the Engine ECU and run the machine to verify the engine power loss derate has been lifted.