Case IH 19798 (DTC FB9F) - ECU – Engine Control Unit (ECU): SCR Inducement: Level 3 (creep mode), triggered by DEF/AdBlue Quality fault.

This code indicates that the Selective Catalytic Reduction (SCR) system has detected poor-quality Diesel Exhaust Fluid (DEF/AdBlue) multiple times. Specifically, the inducement system locks the machine into a severe derate (Level 3 / creep mode) due to 3 detections of poor DEF quality within a 40-hour operating window. When this occurs, engine power is severely limited, and vehicle speed is restricted.

• MAXXUM T4E
• 240 Series Axial-Flow Combines (7240, 8240, 9240)
• Farmall (40, 45, 50, 115U)
• Magnum (250-380)
• Puma (150-240)
• Quadtrac (470-620)
• Patriot (3230, 3330, 4430)

1. 1

   Test DEF Quality: Use a DEF refractometer to verify the urea concentration is at the required 32.5%. Check for water dilution, diesel fuel contamination, or incorrect fluids.

2. 2

   Inspect the DEF Quality Sensor: Check the sensor and wiring harness for damage, corrosion, or voltage irregularities. Contaminated DEF can cause chemical reactions that permanently damage the sending unit sensor.

3. 3

   Check for Dosing Interruptions: Ensure the DEF lines are not frozen, blocked, or leaking, which can trigger false quality or consumption faults.

4. 4

   Check for Tampering: Ensure the SCR monitoring system has not been tampered with, as this can trigger parallel inducement codes.

5. 5

   Check the EGR Valve: Verify the EGR valve is not blocked, as this can sometimes trigger related SCR inducement faults.

1. 1

   Drain and Flush

   If the DEF is contaminated or degraded, completely drain the DEF tank. Flush the tank and dosing lines to remove any residual contaminated fluid.

2. 2

   Replace Damaged Sensors

   If the DEF quality sensor or DEF head unit was damaged by contamination or has failed electronically, replace the unit.

3. 3

   Refill System

   Refill the tank with fresh, known-good DEF/AdBlue.

4. 4

   Emergency Move (If necessary)

   If the machine is stranded, an emergency re-start can be commanded. This allows 30 seconds of operation without power loss to move the machine before it automatically reduces to low idle speed again.

5. 5

   Reset the Inducement Lock

   Because the system is hard-locked (Level 3), simply replacing the fluid will not clear the code. A certified technician must connect the Case IH Electronic Service Tool (EST) and run the "Engine Restart Counter Reset" (which addresses the parallel DTC FBBF 3436) to unlock the inducement system and restore full engine power.