Case IH 3787 – Engine Control Module (ECM) / EDC: Diesel Particulate Filter (DPF): Signal range check flow resistance of the particulate filter - very high

The differential pressure sensor has detected that the exhaust backpressure across the DPF has exceeded the maximum allowable threshold. The filter is severely restricted by excessive soot or ash accumulation, and the system has likely locked out standard automatic regeneration to prevent a thermal event or engine damage.

• Farmall
• skid steer
• Maxxum
• Puma
• Steiger
• Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)

1. 1

   Check the DPF Differential Pressure Sensor: Verify the sensor's supply voltage and signal voltage. Ensure the sensor itself hasn't failed or drifted out of range.

2. 2

   Inspect Sensor Hoses: Check the pressure sensor hose lines (tubes running from the exhaust to the sensor) for blockages, melting, cracks, or leaks.

3. 3

   Check for Related Codes: Look for accompanying codes like 3789 (Regeneration duration exceeds maximum allowed) or 3766 (DPF Differential Pressure Sensor failure).

4. 4

   Evaluate Soot/Ash Load: Use the Case IH Electronic Service Tool (EST) to check the calculated soot load and the time interval since the last DPF ash service.

1. 1

   Remove the DPF

   Carefully unbolt and remove the Diesel Particulate Filter assembly from the exhaust line.

2. 2

   Clean or Replace

   The DPF must be physically cleaned (professional pneumatic/thermal ash cleaning) or replaced entirely.

3. 3

   Reinstall Components

   Reinstall the cleaned or new DPF using new exhaust gaskets. Reconnect the differential pressure sensor lines.

4. 4

   Reset Parameters

   You must use the Case IH Electronic Service Tool (EST) to reset the engine controller parameters. This resets the self-learning parameters and tells the ECM that the soot/ash load is back to zero.