Case IH 19154 (DTC 325A) - ECU – DCU (Dosing Control Unit) / ACM (Aftertreatment Control Module): DEF/AdBlue supply module pump temperature is too low to activate pump / UREA Pump speed - pump motor unplugged - P208B reagent-pump not delivering

This code indicates that the DEF (Diesel Exhaust Fluid) supply module is unable to activate the pump. This is typically caused by one of two conditions: 1. The DEF fluid temperature is reading too low for the pump to safely operate, meaning the system's heating circuit has failed to thaw the fluid. 2. The pump motor is electrically unplugged, blocked by crystallized DEF, or experiencing severe speed deviation.

• MAXXUM T4E
• Magnum (180-380)
• Steiger/Quadtrac (350-620)
• Puma
• Maxxum
• Farmall
• Optum
• Axial-Flow 240 Series (7240, 8240, 9240)
• Axial-Flow 130/230 Series (5130-9230)
• Patriot (4430)
• Titan Floaters
• Farmlift Telehandlers
• CX-Series Excavators

1. 1

   Reboot the System: Turn the machine completely off and back on. Sometimes the Aftertreatment Control Module just needs a key cycle to reset the sensors.

2. 2

   Check the Coolant Control Valve (CCV) / Heater Valve: The DEF system relies on engine coolant flowing through a control valve to heat the DEF tank and pump. Ensure the CCV is not stuck closed (which prevents thawing) or stuck open (which boils the DEF). Feel the coolant lines running to the DEF tank to see if they are warm.

3. 3

   Inspect Electrical Connections: Because the code can trigger for a "pump motor unplugged" condition, verify the wiring harness and electrical connector at the DEF supply module are secure and free of corrosion.

4. 4

   Check for Crystallization: DEF crystallization blockages at the filter or injector are frequently misdiagnosed as a failed pump. Inspect the pump housing and lines for white urea crust.

1. 1

   Drain engine coolant

   If the Coolant Control Valve is faulty: Drain the engine coolant below the level of the CCV.

2. 2

   Remove CCV retaining bolts

   Remove the retaining bolts securing the coolant control valve support.

3. 3

   Disconnect coolant hoses

   Disconnect the coolant hoses (note the orientation, as reversing the hoses will cause continuous hot water circulation and overheat the DEF tank).

4. 4

   Install new CCV

   Install the new CCV and torque the retaining bolts to spec (approx. 73 - 80 lb-ft depending on the model).

5. 5

   Refill coolant and clear code

   Refill the coolant and clear the fault code.

6. 6

   Drain DEF tank and flush housing

   If the DEF Supply Module (Pump) has failed internally: Drain the DEF tank completely and flush the external housing face with clean distilled water to prevent dirt from entering the high-pressure fluid loops.

7. 7

   Disconnect pump connections

   Disconnect the electrical connector, the two coolant lines, and the three DEF fluid connectors from the pump assembly.

8. 8

   Remove DEF supply module

   Remove the DEF supply module from its mounting bracket (either tank-mounted or remote frame-mounted).

9. 9

   Install new DEF supply module

   Install the new DEF supply module. If replacing the internal filter only, use the specialized extraction tool to avoid scratching the inner walls of the pump housing.

10. 10

    Refill DEF tank

    Refill the tank with fresh, high-quality DEF (32.5% urea / 67.5% deionized water).

11. 11

    Clear DTCs and run test

    Use an Electronic Service Tool to clear the DTCs and run a system prime/dosing test.