New Holland ENG 3433 – Engine Control Unit (ECU): Diesel Particulate Filter (DPF): Inducement less severe derating level

The Engine Control Unit (ECU) has detected a malfunction or excessive soot/ash accumulation in the Diesel Particulate Filter (DPF) system. This initiates a 'less severe derating level' that actively reduces engine torque and power output to protect the engine. If ignored, it will escalate to code 3434.

• T4.75
• T4.85
• T4.95
• T4.105
• T4.115
• T5.95
• T5.105
• T5.115
• T6 Series
• T7 Series
• T8 Series
• Workmaster 50
• Workmaster 55
• L213
• L215
• L216
• L221
• L225
• L228
• L230
• L316
• L321
• L328
• C227
• C232
• C237
• C238
• C327
• C332
• C337
• W50C
• W60C
• W70C
• W80C
• CX Series

1. 1

   Scan for accompanying codes using the New Holland Electronic Service Tool (EST) to check for other DPF-related codes indicating DPF overload (e.g., 3426), flow resistance issues (e.g., 3766, 3786, 3790), or sensor failures (e.g., 3656, 3796).

2. 2

   Inspect the DPF differential pressure sensor and ensure the metal/rubber hose lines connecting it to the exhaust are not melted, cracked, or clogged with soot.

3. 3

   Check current DPF soot and ash accumulation percentages using the diagnostic tool.

4. 4

   Verify exhaust gas temperature (EGT) sensors are reading correctly, as the engine must reach high temperatures to perform a regeneration.

1. 1

   Address Sensor/Hardware Faults

   If the diagnostic checks revealed a faulty differential pressure sensor, damaged pressure hoses, or a failed EGT sensor, replace those components first.

2. 2

   Perform a Forced Regeneration

   If the DPF is overloaded with soot (but not permanently damaged or full of unburnable ash), park the machine in a safe, well-ventilated area. Use the New Holland EST diagnostic tool to command a manual/stationary DPF regeneration.

3. 3

   Clean or Replace the DPF

   If the forced regeneration fails, or if the diagnostic tool shows the filter is at its maximum ash capacity (ash cannot be burned off), the DPF must be removed. It must either be sent to a specialized facility for pneumatic/thermal ash cleaning or replaced entirely.

4. 4

   Reset the ECU Accumulators

   If the DPF is cleaned or replaced, you must use the diagnostic tool to reset the DPF soot and ash accumulators to zero. If skipped, the ECU will still think the filter is clogged and the 3433 derate code will remain active.

5. 5

   Clear Codes and Test

   Clear all inactive fault codes and test drive the machine under a heavy load to ensure the derate is lifted and the inducement code does not return.