New Holland ENG 3766 – ENGINE: Diesel Particulate Filter (DPF) Pressure Sensor: Fault check for the pressure sensor plausibility

The Engine Control Unit is receiving a signal from the DPF differential pressure sensor that does not make sense given the current engine operating conditions (implausible reading). This usually points to a failing sensor, a blocked/leaking sensor hose, or a wiring issue.

• TD5.85
• TD5.95
• TD5.105
• TD5.115
• T5.95
• T5.105
• T5.115
• L220
• SR175

1. 1

   Inspect the DPF pressure sensor hoses for cracks, melting, blockages (soot buildup), or disconnection.

2. 2

   Check the electrical connector at the DPF pressure sensor for corrosion, pushed-out pins, or moisture, and verify correct reference voltage and ground from the EDC.

3. 3

   Check for exhaust leaks upstream of the DPF that could skew the pressure differential readings.

1. 1

   Disconnect battery

   Turn off the machine and disconnect the battery to prevent electrical shorts.

2. 2

   Locate sensor

   Locate the DPF Differential Pressure Sensor (typically mounted on a bracket near the DPF assembly, with two hoses routing to the exhaust pipe).

3. 3

   Disconnect harness

   Disconnect the electrical harness connector from the sensor.

4. 4

   Remove pressure hoses

   Carefully loosen the clamps and remove the two pressure hoses from the bottom of the sensor. Note which hose goes to the upstream port and which goes to the downstream port.

5. 5

   Remove sensor

   Unbolt the sensor from its mounting bracket and remove it.

6. 6

   Install new sensor

   Install the new sensor onto the bracket.

7. 7

   Reconnect pressure hoses

   Reconnect the pressure hoses to their correct ports and secure them with clamps.

8. 8

   Reconnect harness

   Reconnect the electrical harness.

9. 9

   Reconnect battery

   Reconnect the battery.

10. 10

    Clear fault code

    Use a compatible diagnostic service tool to clear the ENG 3766 fault code. Note: If the Engine Controller (EDC) was also replaced or flashed during this process, you must follow the appropriate service tool procedure to restore self-learning parameters.