Case IH 19719 – Engine Control Unit (ECU): Minimum rail pressure exceeded for tank lo detection

This code indicates that the common rail fuel pressure has dropped below the minimum required threshold, and the system has detected this condition in conjunction with a low fuel tank level. Essentially, the engine is experiencing a low fuel rail pressure event, and the system suspects fuel starvation due to an empty or near-empty fuel tank.

• Tier 4b
• Magnum 280
• Magnum 370
• Maxxum 110
• Maxxum 115
• Maxxum 120
• Maxxum 125
• Maxxum 130
• Maxxum 140
• N-Series Loaders
• N-Series backhoes

1. 1

   Verify Fuel Level: Physically verify the fuel level in the tank. Do not rely solely on the gauge.

2. 2

   Check for Supply Restrictions: Inspect the low-pressure fuel supply side for a clogged primary/secondary fuel filter, kinked fuel line, or air entering the system.

3. 3

   Perform an Injector Leak-Off (Back-Leak) Test: Measure the fuel volume returning from each injector and the high-pressure pump to check for excessive return flow.

4. 4

   Test the Fuel Pressure Relief Valve (PRV): Check if the pressure limit valve is leaking fuel into the return line under normal operating pressures.

5. 5

   Test the Fuel Metering Unit (FCA/MPROP): Unplug the Fuel Control Actuator on the high-pressure pump during a hard start/no start to see if the engine starts, indicating a sticking or failing FCA.

1. 1

   Resolve Fuel Starvation

   Fill the fuel tank. Bleed and prime the fuel system to ensure all air is purged from the low-pressure lines.

2. 2

   Replace Filters

   Replace the primary and secondary fuel filters to rule out a supply-side restriction.

3. 3

   Warm Up and Test

   If the engine runs, warm it up and run a "Fuel System Verification Test" using a diagnostic scanner to monitor live desired vs. actual rail pressure.

4. 4

   Replace Faulty High-Pressure Components

   If the back-leak test reveals the Pressure Relief Valve is popping open too early or leaking, replace the valve (Note: Extreme cleanliness is required; microscopic contamination can destroy common rail components). If the Fuel Metering Unit (FCA) is slow to respond or sticking, replace the unit on the high-pressure pump.

5. 5

   Clear Codes

   Use a diagnostic tool to clear the 19719 code and test the machine under load to ensure rail pressure maintains the desired setpoint.