Case IH F-653-05 - ECU – Engine Control Unit (ECU): Open load error of injector in cylinder 3

The control module has detected an open circuit or abnormally low current draw on the electrical circuit controlling the fuel injector for cylinder number 3.

• MAGNUM AFS Connect
• 240 Series Axial-Flow Combines (7240, 8240, 9240)
• Steiger series (540, 580, 620)
• Quadtrac
• Magnum
• Puma
• Farmall series
• AUSTOFT 9900 sugarcane harvesters

1. 1

   Verify that the tractor battery has not been connected to an external power supply (like a jump box or charger), which can trigger false open-load codes.

2. 2

   Inspect the wiring harness between the ECU and the cylinder 3 electronic injector (Y320-3) for chafed wires, loose pins at the connectors, or corrosion.

3. 3

   Use a multimeter to measure the resistance across the cylinder 3 injector terminals to check for an internal open circuit (infinite resistance).

1. 1

   Disconnect Power

   Disconnect the machine's battery power before servicing the fuel system or ECU wiring.

2. 2

   Repair Wiring (If Applicable)

   If the diagnostic checks revealed a broken wire or loose pin in the harness leading to cylinder 3, repair the connection and re-test.

3. 3

   Remove Faulty Injector

   If the injector solenoid is internally open, remove the valve cover (if required by the specific FPT engine model) and extract the faulty cylinder 3 injector.

4. 4

   Install New Injector

   Install the replacement OEM fuel injector along with new O-rings and sealing washers. Torque the hold-down clamp and fuel lines to OEM specifications.

5. 5

   Program the ECU

   The new injector's specific calibration string (QR code) must be programmed into the Engine ECU. Failure to do so will trigger a related fault code (653-13).

6. 6

   Clear Codes and Test

   Reconnect the battery, clear the active fault codes using a diagnostic tool, and test drive the unit at operating temperature to confirm the misfire is resolved and the code does not return.