New Holland NH 3047 – Engine ECU: Adapt.cylinder balancing Cylinder 2 - SOURCE HIGH

This code indicates an issue with the adaptive cylinder balancing for Cylinder 2. The Engine Control Unit (ECU) monitors the rotational speed of the crankshaft to determine the power contribution of each cylinder. To maintain smooth engine operation, it adjusts the fuel delivery (injector trim/duration) to each cylinder. 'SOURCE HIGH' typically means the ECU is commanding maximum fuel delivery compensation for Cylinder 2 because it detects a weak or misfiring cylinder, or there is a high voltage condition or a short-to-battery in the electrical circuit for the Cylinder 2 fuel injector.

• T6 Series
• T7 Series
• T7.210
• T8 Series
• T8.320
• T9 Series
• CR Series
• CR8.90
• CR9.90
• CX Series
• CX8080
• CX8090
• FR Series
• W-series
• B-series

1. 1

   Wiring & Connector Inspection: Check the wiring harness and connectors between the Engine ECU and the Cylinder 2 injector. Look for chafed wires, open circuits, or a short to the battery (high source).

2. 2

   Cylinder Balancing Test: Use the CNH Electronic Service Tool (EST) to run a manual cylinder balancing test and a compression test. This will verify if Cylinder 2 is genuinely underperforming compared to the others.

3. 3

   Leak-off Test: Check for excessive fuel leakage from the overpressure valve in the common rail or the injector return lines. Remove the fuel return lines to observe if Cylinder 2 is bypassing too much fuel.

4. 4

   Injector Swap Test: Swap the Cylinder 2 injector with the injector from a known good cylinder (e.g., Cylinder 1). Re-run the balancing test. If the fault code moves to the new cylinder (e.g., NH 3043 for Cylinder 1), the injector is faulty. If the code remains on Cylinder 2, the issue is related to engine compression or the wiring harness.

1. 1

   Disconnect Power

   Turn off the machine and disconnect the battery to prevent electrical spikes.

2. 2

   Harness Repair

   If the diagnostic checks revealed a short-to-battery or damaged wiring on the Cylinder 2 circuit, repair or replace the injector wiring harness.

3. 3

   Replace the Injector

   If the injector failed the swap test or leak-off test, remove the faulty Cylinder 2 fuel injector. Clean the injector bore thoroughly and install the new injector with new O-rings and a new copper sealing washer. Torque the hold-down clamp to OEM specifications.

4. 4

   Program the Injector Trim Code

   Use the CNH EST diagnostic tool to enter the new trim code (IQA/Trim code) printed on the new injector into the Engine ECU. If this step is skipped, the ECU cannot properly balance the cylinder.

5. 5

   Bleed the Fuel System

   Prime the fuel system to remove any air introduced during the repair.

6. 6

   Clear Codes and Test

   Reconnect the battery, clear the NH 3047 fault code using the diagnostic tool, and run the engine at operating temperature to verify the repair.