Case IH 3780 – Engine Control Module (ECM): Engine Protection : Engine protection active due to particulate filter

This code indicates that the engine has entered a protective derate or "limp mode" to prevent catastrophic damage to the engine or the exhaust aftertreatment system. This is triggered when the Diesel Particulate Filter (DPF) reaches a critical soot/ash load, fails to regenerate, or registers an abnormal differential pressure.

• Farmall 75C
• Farmall 85C
• Farmall 105C
• Quantum
• Puma
• SR160
• 580SN

1. 1

   Check for accompanying codes (e.g., 3781/3782, 3783/3784, 3774/3777, 3765/3766) which indicate specific DPF failures.

2. 2

   Monitor live data for the DPF Delta Pressure Sensor. High pressure indicates a clogged filter; zero or erratic readings indicate a sensor or hose fault.

3. 3

   Physically inspect the rubber/metal hoses running from the exhaust to the differential pressure sensor for melting, cracking, or carbon blockages.

4. 4

   Use the diagnostic tool to view the calculated soot and ash accumulation levels in the ECM.

1. 1

   Address Sensor/Hose Faults First

   If codes 3765 or 3766 are present, clear any blockages in the differential pressure sensor hoses or replace the sensor.

2. 2

   Attempt Forced Regeneration

   If the soot load is high but still within the safe regenerable threshold, use the CNH EST diagnostic tool to initiate a parked/forced DPF regeneration.

3. 3

   Clean or Replace the DPF

   If the diagnostic tool indicates the ash load has exceeded the limit (Code 3774) or the maximum number of locked regenerations has been reached (Codes 3783/3784), a forced regeneration will be locked out to prevent a fire. The DPF must be physically removed from the exhaust system. Send the DPF to a certified facility to be professionally baked and blown out (ash removal), or install a new OEM replacement DPF.

4. 4

   Reset ECM Timers

   Once the DPF is cleaned or replaced, you must use the CNH diagnostic tool to reset the DPF ash/soot accumulation timers. If this step is skipped, the ECM will still believe the filter is clogged.

5. 5

   Clear Codes

   Clear fault code 3780 and test run the machine under load to ensure the engine protection mode has deactivated and differential pressure is within normal limits.