Iveco 018D – Engine Control Unit (ECU): Toxic emissions of nitrogen oxides (NOx) above the first threshold

The vehicle's Selective Catalytic Reduction (SCR) system is failing to adequately reduce NOx emissions in the exhaust stream, and the downstream NOx sensor is reading values that exceed the primary allowable limit set by emissions regulations.

• Iveco Daily
• Iveco Stralis
• Iveco Eurocargo
• Iveco Trakker

1. 1

   Scan for other active codes related to the AdBlue dosing pump, urea pressure, or specific NOx sensor circuit faults (e.g., short circuits or heating element failures)

2. 2

   Monitor live data of the upstream and downstream NOx sensors using a diagnostic scanner to check for erratic or implausible data

3. 3

   Inspect the AdBlue tank level and fluid quality

4. 4

   Inspect the AdBlue dosing valve/injector and exhaust pipe for severe urea crystallization or blockages

5. 5

   Perform a dosing quantity test using a diagnostic tool to verify the correct amount of urea is being injected into the exhaust stream

6. 6

   Inspect the exhaust system for leaks upstream of the SCR catalyst and NOx sensors

1. 1

   Address Physical Blockages

   If urea crystallization is found on the AdBlue dosing valve or inside the exhaust pipe, remove the dosing injector and clean the port using warm water and appropriate cleaning tools.

2. 2

   Replace Faulty Components

   If the diagnostic tests prove the AdBlue dosing module is failing to build pressure or inject fluid, replace the dosing module/pump. If the dosing system is working perfectly but the NOx sensor is reading out of range or failing to heat up, replace the affected NOx sensor.

3. 3

   Reassemble and Reconnect

   Install the new parts, ensuring all electrical connectors are secure and exhaust fittings are torqued to specification to prevent leaks.

4. 4

   Clear Codes and Reset Adaptations

   Connect the diagnostic scanner, clear the 018D fault code, and reset the SCR system adaptations/learned values if a new NOx sensor or dosing pump was installed.

5. 5

   Test Drive

   Perform a test drive consisting of at least 3 driving cycles to allow the SCR system to reach operating temperature and verify that the MIL (Malfunction Indicator Lamp) remains off and the code does not return.