John Deere 3251.03 – ECU: DPF Differential Pressure Signal Out of Range High

The signal from the Diesel Particulate Filter (DPF) Differential Pressure Sensor indicates a voltage that is above the normal operating range, usually indicating a short to 12 volts in the sensor circuit.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 5090M
• 5115M
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 6105M
• 6R series
• 7R series
• 8R series
• 7250R
• 8345R
• 9RT track tractors
• 9470RT
• 9520RT
• 9570RT
• 204L Compact 4WD Loader
• 304L Compact 4WD Loader
• excavators
• graders
• 7400A TerrainCut
• 7500A E-Cut Hybrid mower
• 7700A E-Cut Hybrid mower
• 8000A E-Cut Hybrid mower

1. 1

   Visually inspect the DPF differential pressure sensor, its electrical connector, and the wiring harness for visible damage, melting, or corrosion.

2. 2

   Use a multimeter to test the sensor's wiring circuit for a short to a 12-volt power source (the primary trigger for this code).

3. 3

   Using a diagnostic tool (like Service ADVISOR), check the sensor's live data with the engine off. The differential pressure should read zero. An abnormally high pressure or voltage indicates the sensor is likely internally shorted.

4. 4

   Inspect the pressure sensor tubes/lines running from the exhaust pipe to the sensor for blockages (soot buildup) or physical damage.

1. 1

   Safety First

   Ensure the machine is turned off, the battery is disconnected, and the exhaust system has completely cooled down, as DPF components operate at extreme temperatures.

2. 2

   Locate the Sensor

   Find the DPF differential pressure sensor, which is typically mounted on or near the DPF canister in the exhaust aftertreatment system.

3. 3

   Repair Wiring

   If your diagnostic checks revealed a short to 12V in the harness, repair or replace the damaged section of the wiring harness.

4. 4

   Replace the Sensor

   If the wiring is intact, the sensor itself has failed. Disconnect the weatherproof electrical connector. Unbolt the sensor and carefully disconnect the pressure lines. Install the new sensor and reconnect the lines and wiring harness.

5. 5

   Clear Codes and Calibrate

   Reconnect the battery. Use a diagnostic tool to clear the 003251.03 fault code from the ECU.

6. 6

   System Re-test

   Start the engine and let the system run through a calibration cycle to confirm the sensor is reading accurately and the code does not return.