New Holland ENG 3427 – Engine ECU: Diesel Particulate Filter (DPF): Signal range check flow resistance of the Particulate Filter - Low

The engine controller is detecting a lower-than-expected pressure drop across the Diesel Particulate Filter. This usually indicates that the DPF has been physically removed/hollowed out, there is a severe exhaust leak, a differential pressure hose has fallen off or ruptured, or the differential pressure sensor itself has failed.

• Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)
• L230
• C232
• Tractors
• Machines with FPT F5C engines

1. 1

   Verify that the Diesel Particulate Filter (DPF) is physically present and has not been removed, bypassed, or hollowed out

2. 2

   Check the differential pressure sensor hose lines connecting the DPF to the sensor for detachment, cracks, melting, or leaks

3. 3

   Inspect the wiring harness and connector at the DPF differential pressure sensor for corrosion, backed-out pins, or chafing

1. 1

   Secure the Machine

   Park the machine on a level surface, turn off the engine, and allow the exhaust system to cool completely to avoid burns.

2. 2

   Inspect and Repair Hoses

   Locate the DPF differential pressure sensor and trace the hoses down to the DPF housing. If a hose is blown off, reattach it and secure it with a clamp. If a hose is brittle or cracked, replace the hose line.

3. 3

   Disconnect Sensor

   If the DPF is intact and the hoses are in good condition, the differential pressure sensor is likely faulty. Disconnect the electrical connector from the sensor.

4. 4

   Remove the Sensor

   Remove the mounting hardware securing the sensor and disconnect the pressure hoses from the sensor nipples.

5. 5

   Install the New Sensor

   Mount the new OEM differential pressure sensor, reattach the hoses (ensuring they are routed correctly to the upstream and downstream ports), and plug in the electrical connector.

6. 6

   Reset the ECU

   Use a New Holland diagnostic service tool to clear the active ENG 3427 fault code. Navigate to the configuration menu and perform a reset/relearn procedure for the new DPF differential pressure sensor so the Engine ECU can calibrate to the new component.