Case IH 17871 (F-651-03) - ECU – Engine Control Unit (Engine ECU / EDC): Short circuit error of injector in cylinder 1

The engine control system has detected an electrical short circuit on the low or high side of the wiring circuit that controls the fuel injector for cylinder number 1. The short could be a short-to-ground, a short-to-power, or an internal short within the injector's solenoid itself.

• VESTRUM CVX
• Case IH Austoft 9900 and 9000 Series
• Case IH Axial-Flow 240 Series Combines (7240, 8240, 9240)
• Case IH Puma and Farmall Series

1. 1

   Inspect the engine wiring harness connecting the Engine ECU to the cylinder 1 fuel injector. Look for chafed wires, melted insulation, or pinched lines against the engine block or valve cover.

2. 2

   Perform a harness continuity test by disconnecting the harness at the Engine ECU and at the cylinder 1 injector. Use a digital multimeter to test the injector control wires for a short to ground, a short to a power source, or a short between the two wires.

3. 3

   If the wiring harness tests good, measure the internal resistance across the pins of the cylinder 1 injector itself. An out-of-spec or near-zero resistance reading indicates the injector solenoid has failed internally.

1. 1

   Disconnect Power

   Turn off the machine and disconnect the negative battery cable to prevent electrical damage.

2. 2

   Repair Wiring (If Applicable)

   If the diagnostic tests revealed a short in the wiring harness, repair the damaged section using OEM-approved waterproof splices, or replace the engine wiring harness entirely.

3. 3

   Access the Injector (If replacing)

   If the injector is internally shorted, remove the engine valve cover (required for FPT Cursor engines where injectors are located under the cover) to access the cylinder 1 fuel injector.

4. 4

   Remove the Faulty Injector

   Disconnect the injector's electrical connector. Remove the hold-down clamp/bolt and carefully extract the faulty injector from the cylinder head.

5. 5

   Install the New Injector

   Clean the injector cup. Install the new or remanufactured injector using new O-rings and copper sealing washers. Torque the hold-down clamp to the exact OEM specification found in your engine's service manual.

6. 6

   Reassembly

   Reconnect the injector wiring harness and reinstall the valve cover with a new gasket.

7. 7

   Clear Codes

   Reconnect the battery. Turn the ignition on and use a Case IH diagnostic tool (EST) to clear the 17871 (F-651-03) fault code.

8. 8

   Test Run

   Start the engine and verify smooth operation. Ensure the fault code does not return under load.