New Holland 3320 – DCU: Urea Level in Tank Below 10%

The Dosing Control Unit (DCU) has detected that the Diesel Exhaust Fluid (DEF) or urea level in the tank has dropped below the 10% threshold. This is a critical warning that affects the proper functioning of the emission control system. Ignoring this warning can lead to the engine entering a derated power mode or a no-start condition.

1. 1

   Visually inspect the DEF tank to confirm if the fluid level is actually low

2. 2

   Ensure that no incorrect or contaminated fluid has been accidentally added to the DEF tank

3. 3

   Inspect the wiring harness and connectors leading to the DEF tank level sensor for damage, corrosion, or loose connections

4. 4

   Use a compatible diagnostic scan tool to read fault codes and monitor the DEF level sensor data in real-time to verify sensor accuracy

5. 5

   Check for any Technical Service Bulletins (TSBs) related to the DEF system or generic fault code P203F for your specific machine

1. 1

   Refill DEF tank

   If the DEF level is low, refill the tank with new, high-quality, uncontaminated Diesel Exhaust Fluid. Clear the fault code with a diagnostic tool and operate the machine to see if the code returns.

2. 2

   Repair wiring and connectors

   If any damaged wiring or corroded connectors were found during inspection, repair or replace them as necessary. Ensure all connections are secure.

3. 3

   Replace DEF level sensor

   If the tank is full, fluid is correct, and wiring is intact, replace the faulty DEF level sensor. Drain the DEF tank, disconnect the electrical connector and lines, remove the retaining ring/bolts, and carefully remove the old sensor. Install the new sensor ensuring a proper seal, reconnect everything, refill the tank, and clear the fault code.

4. 4

   Update PCM/ECM software

   In rare cases, the issue might be a software glitch. Check with a New Holland dealer to see if a Powertrain Control Module (PCM) or Engine Control Module (ECM) software update is available.