New Holland DCU 19749 – DCU: Too high UREA Temperature in Pump module or Leakage test failed

The system has detected a failure during the dynamic or static urea (DEF) leakage test. This means there is a loss of pressure, an internal/external leak of Diesel Exhaust Fluid (DEF) in the dosing system, a stuck Urea Dosing Valve (UDV), or the pump module is overheating due to a lack of fluid flow.

• New Holland T6
• New Holland T7
• New Holland T8
• New Holland T9
• New Holland TS6.120

1. 1

   Inspect the DEF tank for frozen fluid, debris, or a low fluid level.

2. 2

   Measure DEF concentration to ensure it is 32.5% automotive-grade urea to 67.5% distilled water. Drain and replace if incorrect.

3. 3

   Visually inspect all DEF supply lines, fittings, and the DEF pump for external fluid leaks, kinks, or blockages.

4. 4

   Remove the dosing injector and inspect the Urea Dosing Valve (UDV) tip and mixing chamber for white scale build-up.

5. 5

   Use a diagnostic tool to run a Urea Dosing System Test (UDST), Urea Dosing Leak Check (UDLC) to ensure 9 bar pressure, and a Urea Dosing Valve Check (UDVC).

1. 1

   Clean the Dosing Valve

   If white scale deposits are found on the Urea Dosing Valve (UDV) tip or in the mixing chamber, clean the components thoroughly.

2. 2

   Repair Lines/Fittings

   If external leaks are found on the supply lines, replace the damaged lines or fittings and ensure all connectors are tight and undamaged.

3. 3

   Replace the DEF Pump

   If the DEF pump is leaking externally, or if it fails the pressure/volume tests (internal failure) and no other faults are found, the pump module must be replaced. Note: Do not replace the pump unnecessarily; ensure the root cause is not just a clogged line or bad fluid.

4. 4

   Reprogramming

   If the DEF pump (Denoxtronic Supply Module) is replaced, the new module may need to be programmed to the vehicle.

5. 5

   Clear and Verify

   Clear the fault codes using the diagnostic tool and run a dynamic urea leakage test to verify the system maintains pressure and the repair is successful.