Case IH 19797 (F-5841-16) - ECU – Engine Control Unit (ECU): SCR Inducement: Level 1 (Torque reduction), triggered by DEF/AdBlue quality fault.

The Selective Catalytic Reduction (SCR) system has detected that the Diesel Exhaust Fluid (DEF) / AdBlue in the tank does not meet the required purity or concentration standards (typically 32.5% urea). Because the emissions system cannot function properly with poor-quality fluid, the system triggers a "Level 1 Inducement," which actively reduces engine torque to force the operator to address the emissions fault. If ignored, this will eventually escalate to a Level 3 inducement (severe derate/creep mode).

• VESTRUM CVX
• Axial-Flow Combines (240 Series)
• Farmall (40-45-50, 110A)
• Puma
• Optum
• Magnum
• Steiger
• Quadtrac
• Austoft 9900
• TR340
• SV340B

1. 1

   Test DEF Quality: Use a DEF refractometer to test the fluid currently in the tank. It must read exactly 32.5% urea concentration.

2. 2

   Inspect for Contamination: Check the DEF tank for visual signs of contamination, such as water, diesel fuel, or dirt, which can cause chemical reactions that damage the sending unit.

3. 3

   Check for Related Codes: Verify if there are other active codes related to the DEF dosing module, NOx sensors, or the DEF quality sensor itself. A failing DEF Head Unit/Quality Sensor can erroneously trigger this code even if the fluid is good.

1. 1

   Drain the Tank

   Completely drain the DEF tank to remove the degraded or contaminated fluid.

2. 2

   Flush the System

   If severe contamination (like diesel fuel or heavy debris) is found, flush the tank with distilled water or fresh DEF.

3. 3

   Replace the DEF Filter

   Remove and replace the DEF filter assembly to ensure no residual contaminants restrict the dosing module or reach the SCR catalyst.

4. 4

   Refill

   Fill the tank with fresh, high-quality DEF that meets the ISO 22241 standard.

5. 5

   Clear Codes and Reset

   Connect a diagnostic service tool to clear the fault codes. You may need to run an SCR system test or a stationary regeneration to allow the DEF quality sensor to sample the new fluid, verify the repair, and lift the Level 1 torque reduction inducement.

6. 6

   Sensor Replacement (If applicable)

   If the fluid was tested and found to be perfect but the code persists, the DEF Quality Sensor / Head Unit has likely failed and must be replaced.