Case IH 19126 (DTC FF9F) - ECU – Engine Control Unit (ECU): SCR Inducement: Warning, triggered by Tampering fault.

This code indicates that the machine's control system has detected a condition it considers "tampering" or "fraud" regarding the Selective Catalytic Reduction (SCR) / Diesel Exhaust Fluid (DEF) emissions system. When this fault is activated, it triggers an "inducement," which is a forced engine power loss (derate) or limitation to low idle speed to ensure emissions compliance.

• MAXXUM T4E
• 240 Series Axial-Flow® Combines
• T7 Series Tier 4B Tractors
• Steiger & Quadtrac Tier 4 Tractors (350, 400, 450, 500, 550, 600)
• Farmall Tractors (e.g., 115U)
• STM N Series Loaders

1. 1

   Scan for Root Cause Codes: Check the ECU for other active SCR/DEF fault codes (e.g., 19141 - diesel fuel in DEF tank, 19144 - CAN timeout error, temperature sensors, or pump speed deviations).

2. 2

   Inspect Wiring and Connectors: Visually inspect the wiring harnesses connecting the DEF quality sensor and the DEF supply module for unplugged connectors, cut wires, or corrosion.

3. 3

   Test DEF/AdBlue Quality: Test the concentration and quality of the DEF fluid in the tank to ensure it has not been diluted with water or contaminated with diesel fuel.

1. 1

   Address the Root Cause

   The underlying "tampering" or "fraud" fault must be physically repaired first. Reconnect any unplugged sensors or repair damaged wiring harnesses.

2. 2

   Address Fluid Contamination

   If the fault was triggered by bad DEF quality, drain the DEF/AdBlue tank completely, flush/clean the tank, and refill it with approved, high-quality DEF/AdBlue.

3. 3

   Emergency Move

   If the machine is stranded due to full power loss, you can perform an "Emergency Re-start." This is enabled after the engine has been commanded to low idle. It allows exactly 30 seconds of operation without power loss to safely move the machine. After 30 seconds, the engine will automatically reduce to low idle speed.

4. 4

   Clear the Fault Code

   Once the physical repair is complete, cycle the controller power. Use a diagnostic scan tool (or the H menu on-board diagnostics via a diagnostic lead) to clear the stored fault codes. The engine power loss will remain active after an engine restart until the system is properly repaired and the code is cleared by a technician.