Case IH 19125 – Engine Control Unit (ECU) / Engine Electronic Module (EEM) and SCR Dosing Control Unit: No Restart due to empty DEF/AdBlue tank

This is a severe Selective Catalytic Reduction (SCR) inducement code. When the Diesel Exhaust Fluid (DEF) / AdBlue tank runs completely dry, the system triggers an engine lock-out (no restart) to comply with emissions regulations.

• Tier 4b
• Case IH 240 Series Axial-Flow Combines
• Case IH Farmall (e.g., 90C, 100C)
• Case IH Maxxum (e.g., 150 Multicontroller)

1. 1

   Verify the actual physical level of the DEF/AdBlue fluid in the tank.

2. 2

   Check the DEF tank level sensor (often integrated into the DEF header unit) to see if it is stuck, failed, or falsely reporting an empty tank.

3. 3

   Inspect the DEF tank level sensor wiring harness for an open circuit, a short to a high source (voltage), or a short to ground.

4. 4

   Check for a blocked or broken suction line, or leaks in the DEF tank that may have caused the fluid to drain unexpectedly.

1. 1

   Refill the Tank

   Fill the DEF/AdBlue tank with high-quality aqueous urea solution (DEF).

2. 2

   Cycle the Key

   Turn the ignition key to the ON position without starting the engine to allow the DEF level sensor to register the new fluid level.

3. 3

   Replace Failed Components (if applicable)

   If the tank was already full and the sensor is defective or the wiring is shorted, replace the DEF Tank Level Sensor / DEF Header assembly or repair the wiring harness.

4. 4

   Clear the Error Log

   Because this is an emissions-related fault that triggers an engine power reduction/lock-out, you must save the error log and then erase it using a diagnostic service tool (such as the CNH EST).

5. 5

   Restart the ECU

   Restart the ECU after erasing the error log to clear the SCR inducement and restore normal engine starting and power.