Case IH 3104 (DTC F445) - ECU – Engine Control Unit (ECU) A-095: Fuel pressure relief valve is open.

The mechanical Pressure Relief Valve (PRV), which is integral to the common fuel rail, is designed to open in the event that excessive rail pressure occurs to prevent damage to the injectors and fuel system. The Engine Control Unit (ECU) senses and counts radical reductions in rail pressure. If the ECU detects that the valve has opened, it logs this fault code.

• MAXXUM T4E
• Magnum MX210
• Magnum MX230
• Magnum MX245
• Magnum MX255
• Magnum MX275
• Magnum MX285
• Magnum 215
• Magnum 245
• Magnum 275
• Magnum 305
• Magnum 335
• Steiger series
• Puma series
• Farmall series
• Axial-Flow 7230
• Axial-Flow 8230
• Axial-Flow 9230
• Axial-Flow 240 series
• Axial-Flow 2377
• Axial-Flow 2388
• Axial-Flow 2577
• Axial-Flow 2588
• Patriot 4420
• Titan 3020
• Titan 3520
• Titan 4020
• Titan 4520
• 570NXT
• 580N
• SR220
• SR250
• SV250
• SV300
• TR320
• TV380

1. 1

   Check fuel supply pressure between the fuel filter and the inlet to the high-pressure pump (should be a minimum of 5 bar / 72 psi with the engine loaded or unloaded).

2. 2

   Check vacuum restrictions between the inlet of the low-pressure pump and the fuel tank (should not exceed 127 mm / 5 inches of Hg).

3. 3

   Check for associated low rail pressure codes (such as P0148, P0087, or P1093) which often accompany a weak or failing pressure relief valve.

4. 4

   Evaluate symptoms: A failing PRV will often cause a noticeable lack of power (due to low rail pressure) and poor fuel economy.

1. 1

   Clean the area

   Thoroughly clean the fuel rail and surrounding area before loosening any fittings. Installation requires extreme cleanliness, as even microscopic contamination can destroy common rail components.

2. 2

   Relieve pressure

   Ensure the engine is off and the high-pressure fuel system has completely depressurized before servicing.

3. 3

   Remove the valve

   Locate the pressure relief valve (limit valve) threaded into the fuel rail. Disconnect the return line and unthread the valve from the rail.

4. 4

   Install the new valve

   Thread the new PRV into the fuel rail and torque to the manufacturer's specific specification (refer to your exact engine model's service manual for the torque value).

5. 5

   Reassemble and prime

   Reconnect the fuel return line. Always use fresh, filtered fuel when priming the system. It is highly recommended to replace the fuel filters at this time.

6. 6

   Clear codes and test

   Clear the 3104 (F445) fault code from the ECU and test run the machine under load to ensure rail pressure remains within specification and the code does not return.