Case IH F-519046-14 - ECU – Engine Control Unit (ECU) / Dosing Control Unit (DCU): SCR Reagent Feeding. SCR monitoring: general pressure check error

The DEF (Diesel Exhaust Fluid) pump is failing to build, stabilize, or maintain the required fluid pressure (typically 5 to 9 bar) needed to inject DEF into the exhaust stream, indicating a pressure drop or an inability to prime.

• MAGNUM AFS Connect
• 240 Series Axial-Flow (7240, 8240, 9240)
• Puma
• Magnum
• Optum
• Steiger
• Maxxum
• Farmall
• Patriot series (3240, 3340)

1. 1

   Verify the DEF tank has adequate fluid and that the fluid is not contaminated, crystallized, or frozen.

2. 2

   Inspect all DEF supply lines for kinks, blockages, or external leaks.

3. 3

   Check the electrical harness and connectors at the DEF pump for corrosion or damage.

4. 4

   Check for a clogged or dried-out DEF filter, which is a common cause of low pressure.

5. 5

   Inspect the suction tube inside the tank (on tank-mounted pump assemblies) for hairline cracks that cause the pump to draw in air instead of fluid.

6. 6

   Use a diagnostic scan tool to command a system pressure test. Rapid pressure decay indicates an internal pump leak, a failed check valve, or a stuck-open dosing injector.

1. 1

   Clean the Area

   Thoroughly clean the area around the DEF pump/supply module and fluid connectors using a suitable solvent to prevent dirt from entering the SCR system.

2. 2

   Address Leaks & Filters

   If an external leak is found at a fitting, repair or replace the line. If no leaks are found but pressure is low, replace the DEF main filter assembly.

3. 3

   Re-prime the System

   If the filter was dried out, allow the new filter/pump to sit in DEF fluid to saturate. Run the leak/pressure test via the diagnostic tool three times to purge air and build pressure.

4. 4

   Replace the Pump

   If the pump motor has failed, the internal suction tube is cracked, or it still cannot hold pressure, the DEF Supply Module must be replaced. Disconnect the battery, drain the DEF tank (if applicable), disconnect the electrical harness and fluid lines, unbolt and remove the pump, and install the new pump ensuring all O-rings and seals are seated correctly.

5. 5

   Clear Codes and Test

   Reconnect the battery, clear the F-519046-14 fault code using the diagnostic tool, and run a forced dosing test to verify the system builds pressure and the code does not return.