Case IH 19108 – Engine Control Module (ECM) or Dosing Control Unit (DCU): DEF/AdBlue supply module pump motor short circuit to battery failure

The control system has detected that the electrical circuit supplying power to the DEF (Diesel Exhaust Fluid) pump motor is shorted to a battery voltage source. This prevents the pump from operating correctly, meaning the system cannot supply DEF to the dosing injector, which will eventually lead to an engine derate or power loss.

• Tier 4b
• 240 Series Axial-Flow Combines (7240, 8240, 9240)
• 130/230 series Combines (5130, 6130, 7130, 7230)
• Farmall
• Magnum (180 through 370)
• Maxxum (110 through 140)
• Puma (130 through 215)
• Steiger (350 through 600)
• Patriot (4430)
• Titan series
• Farmlift series

1. 1

   Inspect the wiring harness running from the ECM to the DEF supply module for chafing, melting, or pinched wires that could cause a short to battery voltage.

2. 2

   Disconnect the DEF supply module electrical connector and inspect the pins for corrosion, moisture, or physical damage that could bridge the circuits.

3. 3

   Using a digital multimeter, test the pump motor supply circuit in the harness for continuity to battery power with the module disconnected. If voltage is present, repair the shorted wiring harness.

4. 4

   If the harness tests good, the short circuit is internal to the DEF supply module's pump motor, indicating the module must be replaced.

1. 1

   Turn off the equipment, remove the key, and disconnect the battery to ensure safety and prevent further electrical damage.

2. 2

   Locate the DEF supply module (typically mounted on or near the DEF tank).

3. 3

   Thoroughly clean the area around the module to prevent dirt and debris from entering the DEF system.

4. 4

   Disconnect the electrical wiring harness connector from the DEF supply module.

5. 5

   Disconnect the DEF fluid lines (suction, pressure, and backflow/return).

   Note: Be prepared to catch any spilled DEF fluid and cap the lines immediately to prevent crystallization and contamination.

6. 6

   Remove the mounting bolts securing the DEF supply module to its bracket and remove the faulty unit.

7. 7

   Install the new DEF supply module and tighten the mounting bolts.

8. 8

   Reconnect the DEF fluid lines, ensuring they click into place securely.

9. 9

   Reconnect the electrical harness connector.

10. 10

    Reconnect the battery.

11. 11

    Turn the key on and use a diagnostic scan tool to clear the 19108 fault code.

12. 12

    Run an engine test or command a DEF system prime/dosing test via the scan tool to verify the pump operates without throwing the code again.