ECU 003216.14 – Aftertreatment Inlet NOx Sensor Faulty. John Deere System Advisory.

ECU 003216.14 (ECU 3216.14)

Code: 003216.14

Shortcode: 3216.14


This diagnostic trouble code is activated when the aftertreatment inlet NOx sensor reports a problem with its ability to measure nitrogen oxides in the exhaust gases accurately. This sensor is crucial for assessing the effectiveness of the engine’s emission control system before the gases pass through any aftertreatment systems.


The ECU may alter engine and aftertreatment operations to prevent potential damage or non-compliance with emission regulations due to inaccurate NOx readings.


  • Inspect NOx Sensor: Check the sensor for physical damage, contamination, or connection issues that could affect its performance.
  • Test Sensor Functionality: Utilize diagnostic tools to assess the sensor’s output and responsiveness to ensure it is functioning within specified parameters.
  • Replace Faulty Sensor: If diagnostics confirm the sensor is defective, replace it to restore accurate NOx measurement capabilities.
  • Clear Fault Codes and Reset ECU: After replacing the sensor, clear any related fault codes from the ECU and reset the system to ensure all changes are recognized.
  • Verify System Compliance: Perform a system check to ensure that the emission levels are within the regulatory requirements with the new sensor in place.


Accurate NOx measurement at the inlet of the aftertreatment system is essential for effective emission control. Regular sensor maintenance and prompt replacement of faulty units are critical to maintaining compliance with environmental standards.

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