Case IH 17864 (F-654-04) - ECU – ECU: Short circuit of low side of injector in cylinder 4

The engine's control system has detected an electrical short to ground (or to another circuit) on the return/ground wire (the "low side") of the fuel injector for cylinder number 4. This condition prevents the injector from firing correctly, typically resulting in an engine misfire, rough idling, loss of power, and an active check engine light.

• VESTRUM CVX
• Austoft 9000 series
• Austoft 9900 series
• Axial-Flow 7240
• Axial-Flow 7250

1. 1

   Visually inspect the engine wiring harness leading to the cylinder 4 injector for chafed insulation, melted wires, or rubbing against the engine block or valve cover.

2. 2

   Perform a harness continuity/short test by disconnecting the wiring harness from the ECU and the cylinder 4 injector, then use a multimeter to test the low-side wire for continuity to ground.

3. 3

   Test the injector solenoid resistance across the pins of the cylinder 4 injector and compare the reading to a known good injector (e.g., cylinder 3 or 5) to check for an internal short.

4. 4

   Inspect the ECU and injector connector pins for corrosion, moisture ingress, or bent pins that could bridge the circuit.

1. 1

   Power Down

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

2. 2

   Access the Injectors

   Remove the engine covers or valve cover as necessary to access the fuel injectors and the injector wiring harness on the FPT Cursor 11 engine.

3. 3

   Address Wiring (If Applicable)

   If diagnostics revealed a harness short, carefully open the wire loom, locate the shorted section of the low-side wire for cylinder 4, and repair it using OEM-approved splicing and heat-shrink. Alternatively, replace the entire injector wiring harness.

4. 4

   Replace Injector (If Applicable)

   If the injector is internally shorted: Clean the area around the injector to prevent debris from entering the cylinder. Disconnect the high-pressure fuel line and cap the fittings. Remove the injector hold-down clamp and carefully extract the cylinder 4 injector. Install the replacement injector using new O-rings and a new copper sealing washer. Reinstall the hold-down clamp and high-pressure fuel line, torquing all fittings to FPT/Case IH specifications.

5. 5

   Reassembly

   Reconnect the injector electrical connector and reassemble any removed engine covers. Reconnect the battery.

6. 6

   Clear Codes

   Connect a diagnostic scan tool to the machine, clear the 17864 (F-654-04) fault code from the ECU, and run the engine to verify the misfire is resolved and the code does not return.