Case IH 19910 – Engine Control Unit (ECU): Error in comparing energizing time to maximum value for injector in cylinder 6

This fault code indicates that the Engine Control Unit (ECU) has detected an anomaly during its Zero Fuel Calibration (ZFC) or standard monitoring. The ECU evaluates the energizing time required for the injectors at low idle. If the learned calibration values require an energizing time that exceeds the maximum allowed threshold, this code is triggered. This typically points to a failing injector solenoid, excessive mechanical wear inside the injector, poor electrical connections, or a failing ECU injector driver causing the system to overcompensate.

• Tier 4b
• Case IH Magnum Series (e.g., 180, 190, 200, 240)
• Case IH Maxxum Series (e.g., 110, 120, 130)
• Case IH Puma Series
• Case IH Patriot Sprayers
• Case IH Axial-Flow Combines (e.g., AF4130, AF5130)
• Case N Series Loaders

1. 1

   Inspect the wiring harness and connectors between the ECU and the cylinder 6 injector for chafing, corrosion, or loose pins that could cause high resistance.

2. 2

   Perform an Injector Solenoid Resistance Test using a multimeter (expected: 0.5 to 1.5 ohms across coil pins, and >1000 ohms from either pin to ground).

3. 3

   Connect the Case IH Electronic Service Tool (EST) to perform a cylinder contribution test or an injector cut-out test to verify if cylinder 6 is underperforming.

4. 4

   Check for fuel system restrictions or contamination (e.g., water in fuel, plugged filters, or ULSD varnish) that might cause the ECU to overcompensate.

1. 1

   Disconnect battery

   Disconnect the negative battery cable to ensure safety and prevent electrical shorts.

2. 2

   Remove engine covers

   Remove the valve cover or any upper engine covers necessary to access the fuel injectors.

3. 3

   Disconnect injector connector

   Disconnect the electrical connector from the cylinder 6 fuel injector.

4. 4

   Remove fuel line

   Remove the high-pressure fuel line connected to the injector. Cap the fuel rail and the line fittings immediately to prevent contamination.

5. 5

   Remove hold-down clamp

   Remove the injector hold-down clamp/bolt.

6. 6

   Extract injector

   Carefully extract the injector from the cylinder head.

7. 7

   Clean injector bore

   Clean the injector bore in the cylinder head thoroughly. Ensure the old copper sealing washer is removed and no debris falls into the cylinder.

8. 8

   Install new injector

   Install the new injector, ensuring it is fitted with a new copper sealing washer and new O-rings.

9. 9

   Reinstall hold-down clamp

   Reinstall the hold-down clamp and torque the bolt to the specific OEM torque specification for your engine model.

10. 10

    Install new fuel line

    Install a new high-pressure fuel line (recommended after removal) and torque the fittings to spec.

11. 11

    Reconnect electrical connector

    Reconnect the injector electrical connector.

12. 12

    Reinstall valve cover

    Reinstall the valve cover with a new gasket (if applicable) and any engine covers.

13. 13

    Reconnect battery

    Reconnect the negative battery cable.

14. 14

    Enter calibration code

    Connect the Case IH EST and enter the new injector's calibration code (IQA/trim code, found on the top of the new injector) into the ECU so it can properly calculate energizing times.

15. 15

    Verify repair

    Prime the fuel system, start the engine, and check for leaks. Clear the fault codes and run the engine at low idle to allow the Zero Fuel Calibration to run and verify the repair.