Case IH 19729 – Engine Control Unit (ECU): Set-point of metering unit in idle mode not plausible (tank low condition)

The Engine Control Unit has detected that the Fuel Metering Unit (M-PROP) is operating outside of its expected parameters to maintain the target fuel rail pressure at idle. This is most commonly triggered when the machine is operated with a very low fuel level, which introduces air into the fuel lines or causes fuel starvation.

• Tier 4b
• Case IH agricultural equipment
• Case Construction equipment
• Case N Series Loaders

1. 1

   Verify the actual physical fuel level in the tank, as a faulty electronic sender could mask a tank low condition

2. 2

   Inspect the low-pressure fuel supply lines for air leaks, which is the primary cause of metering unit plausibility faults

3. 3

   Inspect the primary fuel filter/water separator and secondary fuel filter for clogging, restriction, or water contamination

4. 4

   Use the Case IH Electronic Service Tool (EST) to monitor the desired vs. actual fuel rail pressure and the fuel metering unit duty cycle while the engine is idling

1. 1

   Refuel the Machine

   Fill the fuel tank to a sufficient level to eliminate the fuel starvation/tank low condition.

2. 2

   Replace Fuel Filters

   Remove and replace the low-pressure fuel filters and water separators to ensure no restriction is causing the metering unit to overcompensate.

3. 3

   Bleed the Fuel System

   Prime and bleed the low-pressure fuel system to purge any trapped air introduced by running the tank low.

4. 4

   Clear the Code

   Connect the Case IH EST diagnostic tool and clear the inactive 19729 fault code from the Engine ECU.

5. 5

   Test Run

   Start the engine and let it idle. Verify that the actual rail pressure matches the set-point and that the fault code does not return.

6. 6

   Further Action (If Code Returns)

   If the fuel supply is verified good, the system is bled, and the code persists, the Fuel Metering Unit on the high-pressure pump may be mechanically faulty and require replacement.