Case IH 3111 (DTC 2325) - ECU – Engine Control Unit (ECU): Rail pressure sensor value is below minimum offset

The engine control system monitors the fuel rail pressure against offset drift when the engine is at a standstill. If the raw voltage signal from the rail pressure sensor drops below the minimum acceptable limit (e.g., below 351.91 mV for more than 100 ms) during this ambient check, it logs this fault. It essentially means the sensor's baseline calibration has drifted out of range or the sensor has failed.

• MAXXUM T4E
• 240 Series Axial-Flow Combines (7240, 8240, 9240)
• Magnum Tractors 235, 245, 250, 275, 305, 335, 340 (Series 4)
• Steiger / STX Tractors 280, 330, 335
• Puma & Maxxum Tractors 110, 115, 125, 140
• Farmall Tractors 90C, 95A, 100C, 105A, 110C, 110U, 115A, 120C, 120U

1. 1

   Verify the fault is active at engine standstill with the key in the ON position.

2. 2

   Inspect the wiring harness and connector at the fuel rail pressure sensor (B-015) for corrosion, moisture intrusion, or chafed wires causing a short to ground.

3. 3

   Verify that the ECU is supplying the correct 5V reference voltage to the sensor.

4. 4

   Using the Case IH Electronic Service Tool (EST), monitor the raw voltage of the rail pressure sensor with the engine off and pressure bled down. A reading below approximately 350 mV indicates internal sensor failure.

1. 1

   Depressurize

   Turn off the engine and allow the machine to sit so the high-pressure fuel rail can safely drop to ambient pressure.

2. 2

   Disconnect Power

   Disconnect the negative battery terminal to prevent accidental electrical shorts or ECU damage.

3. 3

   Locate the Sensor

   Locate the fuel rail pressure sensor, which is threaded directly into the common fuel rail on the engine block.

4. 4

   Remove the Sensor

   Disconnect the electrical harness from the sensor. Clean the area thoroughly around the sensor base to prevent any dirt or debris from entering the open fuel rail. Use a wrench to carefully unscrew the faulty sensor.

5. 5

   Install the New Sensor

   Thread the new OEM fuel rail pressure sensor into the rail. Torque it strictly to the engine manufacturer's specifications (over-tightening can damage the rail or sensor).

6. 6

   Reassembly

   Reconnect the electrical harness until it clicks securely. Reconnect the battery.

7. 7

   Calibration/Clear Codes

   Turn the ignition key to the ON position (do not crank the engine). Allow the ECU to perform its standstill offset check. Connect your diagnostic tool, clear the 3111 (DTC 2325) fault code, and verify that it does not return.