Case IH 19799 (F-5841-15) - ECU – Engine Control Module (ECM): SCR Inducement: Warning, triggered by DEF/AdBlue Quality fault

The system has detected that the Diesel Exhaust Fluid (DEF) in the tank does not meet the required urea concentration (typically 32.5%), or the DEF quality sensor itself has drifted or failed.

• VESTRUM CVX
• 240 Series Axial-Flow Combines
• Quadtrac / Rowtrac Tractors (e.g., 500 series)
• Magnum series tractors
• Steiger series tractors
• Optum series tractors
• Puma series tractors
• Maxxum series tractors
• Farmall series (40-45-50) with Cab and CVT

1. 1

   Test the DEF fluid using a refractometer to ensure it is exactly 32.5% urea and check for contamination or crystallization.

2. 2

   Inspect the DEF Header and Quality Sensor for physical damage or internal circuit board corrosion caused by ammonia gas.

3. 3

   Check the wiring harness and female electrical connector going to the DEF quality sensor for high resistance, corrosion, or broken wires.

1. 1

   Address fluid issues

   If the DEF is contaminated, crystallized, or diluted, completely drain the DEF tank. Flush the system and refill it with fresh, sealed, ISO 22241-compliant DEF.

2. 2

   Replace sensor or header

   If the fluid is good but the sensor is reading incorrectly due to drift or circuit board corrosion, replace the DEF Quality Sensor or the entire DEF Header Unit.

3. 3

   Repair wiring

   If the connector or harness is damaged, splice in a new OEM pigtail connector or replace the sensor wire harness.

4. 4

   Clear codes

   After the physical repair, use a diagnostic tool to clear the fault codes.

5. 5

   Perform Inducement Validation Restart

   Perform an Inducement Validation Restart (a full power restart mode) to allow the ECM to verify the DEF quality is correct and release the machine from the SCR torque derate.