Case IH F-5841-15 - ECU – Engine Control Unit (ECU) / Engine Control Module (ECM): SCR Inducement: Warning, 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 urea concentration (typically 32.5%) or that the sensor itself is malfunctioning. If left unaddressed, this warning will escalate through inducement levels, eventually resulting in engine torque reduction (Level 1) and a severe power derate or creep mode (Level 3).

• MAGNUM AFS Connect
• 240 Series Axial-Flow Combines (7240, 8240, 9240)
• Farmall series (40-50, 115U)
• Magnum
• Steiger
• Quadtrac (Quadtrac 500)
• Austoft 9900 sugarcane harvesters

1. 1

   Test the DEF Fluid: Extract a sample of the DEF from the tank and test it using a DEF refractometer. It must read exactly 32.5% urea concentration.

2. 2

   Inspect for Sensor Drift/Contamination: Check if the DEF quality sensor is suffering from sensor drift or if ammonia gas has corroded the internal circuit boards.

3. 3

   Check Wiring and Connections: Inspect the DEF quality sensor wire harness and the female electrical connector for corrosion, bent pins, or open circuits.

4. 4

   Check for Software Updates: Check with a dealer to see if an ECM flash is available to bypass the in-tank DEF quality sensor entirely.

1. 1

   Clear Contamination (If Applicable)

   If the DEF fluid tests bad, drain the DEF tank completely, flush the system with distilled water or fresh DEF, replace the DEF filter, and refill with new, high-quality DEF.

2. 2

   Access the DEF Header

   If the fluid is good, the DEF Quality Sensor (which is integrated into the DEF Header unit inside the tank) must be replaced. Locate the DEF tank and clean the area around the top flange to prevent dirt from falling in.

3. 3

   Disconnect Harnesses

   Unplug the electrical connector and disconnect the DEF suction and return lines from the header unit.

4. 4

   Remove the Sensor/Header

   Unbolt the retaining ring or mounting bolts holding the DEF header assembly to the tank and carefully pull the unit out.

5. 5

   Install New Part

   Insert the new DEF Quality Sensor/Header unit into the tank, ensuring the gasket is seated properly to prevent leaks.

6. 6

   Reconnect and Prime

   Reconnect the fluid lines and the electrical harness. Turn the key to the ON position to allow the DEF pump to prime the system.

7. 7

   Clear Codes

   Use a diagnostic tool to clear the F-5841-15 fault code. You may need to perform an Inducement Validation Restart (running the engine at low idle, then full power) to allow the ECU to verify the repair and exit the derate mode.