Case IH 3318 – Engine ECU: Minimum Number of Injections Not Reached - Stop Engine

This fault indicates that the engine control unit has shut down the engine because it cannot maintain the minimum number of fuel injections required to run securely. The ECU features an injector shutoff function that disables a single injector valve or an entire injection bank if a defect is detected in a component. If too many cylinders are shut down by this safety function, the engine can no longer operate safely and is forced to shut down entirely, triggering code 3318.

• Case IH Magnum 235 – 340 (Series 4)
• Case IH Steiger series
• Case IH Puma 150 / 165 CVT (Tier 4B Final)

1. 1

   Check for Primary Fault Codes: Connect the CNH Electronic Service Tool (EST) and look for individual injector or injection-bank errors that triggered the shutoff (e.g., codes 3301 through 3314).

2. 2

   Inspect Wiring and Connectors: Check the injector wiring harness for shorts to ground, shorts to battery, or open circuits.

3. 3

   Check Fuel Rail Pressure: Monitor the fuel metering unit and rail pressure sensor data for extreme positive or negative deviations.

1. 1

   Retrieve Codes

   Hook up the diagnostic laptop and pull all active and stored codes from the Engine ECU.

2. 2

   Isolate the Faulty Cylinder/Bank

   Identify which specific injector or bank is causing the primary fault (e.g., "Cylinder 4 Specific Errors - No Signal").

3. 3

   Perform Electrical Testing

   Disconnect the wiring harness at the affected injector and at the ECU. Use a multimeter to check for continuity, high resistance, or shorts in the harness. Repair or replace the harness if damaged.

4. 4

   Test the Injector

   If the wiring is intact, ohm-test the solenoid on the affected fuel injector. If the resistance is out of specification or the injector has mechanically failed (causing a rail pressure drop), replace the fuel injector.

5. 5

   Verify Fuel Metering

   If no electrical faults are found on the injectors, test the fuel metering unit (M-Prop) on the high-pressure fuel pump to ensure it is supplying the correct rail pressure.

6. 6

   Clear and Test

   After replacing the faulty component, clear all fault codes, prime the fuel system, and run the engine to verify that the minimum injection threshold is met and the engine does not shut down.