Case IH 3815 – Engine Control Module (ECM) / EDC (Electronic Diesel Control): Low efficiency in DPF filter

The engine control system has detected that the DPF is not effectively reducing particulate matter (soot) from the exhaust, or the differential pressure across the filter is outside of the expected operating range. This is typically caused by a face-plugged filter, a cracked/melted internal substrate, or faulty sensor readings.

• Farmall series (85A-115A, 85C-115C, 95U-115U)
• Maxxum series
• Puma series
• Magnum series
• CX series excavators (CX130 to CX800)
• SR series skid steers

1. 1

   Check for related sensor codes (e.g., 3801/3802, 3885, 3838/3839/3840/3841) that could cause a false efficiency reading indicating a sensor failure rather than a failed filter.

2. 2

   Inspect the differential pressure sensor and hoses running from the exhaust to the DPF for blockages (soot buildup), melting, or cracks that would cause inaccurate pressure readings.

3. 3

   Monitor upstream and downstream DPF temperatures during a regeneration cycle using a diagnostic tool. Temperatures must reach the required threshold (typically over 1000°F / 530°C) for effective soot oxidation.

4. 4

   If the exhaust is not getting hot enough, inspect the hydrocarbon injector (if equipped) or the Throttle Valve Actuator (TVA) for proper operation, as these drive the heat required for regeneration.

1. 1

   Resolve Sensor Issues

   If the differential pressure sensor or its hoses are damaged or blocked, replace the sensor and clear the lines.

2. 2

   Perform a Forced Regeneration

   If the sensors are functioning properly, use the Case IH Electronic Service Tool (EST / EASy tool) to perform a forced stationary regeneration. Monitor the soot load and differential pressure.

3. 3

   Clean or Replace the DPF

   If the DPF is face-plugged with ash (which cannot be burned off via regeneration) or if the internal substrate is cracked/melted, the DPF assembly must be removed. It will either need to be sent to a professional facility for ash cleaning or replaced entirely.

4. 4

   Reset the ECM Accumulators

   After cleaning or replacing the DPF, you must use the diagnostic service tool to reset the DPF ash and soot accumulators in the ECM. Failing to do this will cause the code to return immediately.

5. 5

   Validation

   Clear the fault codes and perform a validation test run or a final regeneration to ensure the code does not return.