Case IH 19069 – Engine Control Unit (ECU) / Dosing Control Unit (DCU): Upstream SCR catalyst temperature too high

This fault code indicates that the Exhaust Gas Temperature (EGT) sensor located before (upstream of) the Selective Catalytic Reduction (SCR) catalyst is registering a temperature that exceeds the maximum allowable threshold.

• Tier 4b
• 240 Series Axial-Flow Combines
• Steiger
• Magnum
• Farmall
• SV340
• TR340
• STM N Series Loaders

1. 1

   Connect the CNH Electronic Service Tool (EST) and monitor live data for the upstream SCR temperature sensor. Compare its reading to the downstream SCR temperature sensor and ambient air temperature on a cold engine to check for a shorted or internally failed sensor.

2. 2

   Inspect the wiring harness and connectors leading to the upstream SCR temperature sensor for melted wires, chafing, or a short circuit to battery voltage.

3. 3

   Check for accompanying fault codes related to DEF/AdBlue pressure, NOx sensor plausibility, or exhaust flap actuators (e.g., 19019, 19020, 19066) which may indicate a broader exhaust issue.

4. 4

   Perform a physical exhaust inspection to ensure there are no severe exhaust restrictions or active DPF regeneration failures causing genuine excessive exhaust heat.

1. 1

   Cool Down

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

2. 2

   Locate the Sensor

   Locate the upstream EGT sensor. It is threaded into the exhaust pipe directly before the SCR muffler/catalyst assembly.

3. 3

   Disconnect

   Unplug the electrical connector for the sensor. Inspect the pins on the harness side for corrosion or damage.

4. 4

   Remove the Sensor

   Using an appropriate wrench or sensor socket, carefully unthread the faulty temperature sensor from the exhaust pipe. (Penetrating oil may be required if the sensor is seized).

5. 5

   Install the New Sensor

   Apply a small amount of high-temperature anti-seize compound to the threads of the new sensor (if it does not come pre-applied). Thread it into the exhaust pipe and torque to OEM specifications.

6. 6

   Reconnect

   Plug the sensor's electrical connector back into the engine harness.

7. 7

   Clear and Test

   Connect the diagnostic tool, clear the 19069 fault code, and run the engine. Perform a stationary test run or manual regeneration to verify that the temperature readings are now within the normal operating range and the code does not return.