Case IH F-1675-31 - ECU – ECU: Engine cranked for too long or key switch failure

The system has detected that the starter motor has been engaged for an excessive duration, or there is an electrical malfunction in the ignition key switch circuit (such as the switch sticking in the "Start" position or a short in the wiring).

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1. 1

   Verify Operator Error / Secondary No-Start Conditions: Determine if the engine was simply cranked manually for an extended period because the machine wouldn't start (e.g., due to fuel starvation, loss of prime, or extreme cold). If so, the code is a symptom of a different problem.

2. 2

   Inspect the Ignition Switch: Check the physical key switch on the console. Does it feel loose, worn out, or does it physically stick in the "Crank/Start" position when released?

3. 3

   Check the Starter Relay: Ensure the starter relay is not sticking closed, which would cause the engine to continue cranking after the key is released.

4. 4

   Wiring Harness Inspection: Test the wiring between the ignition switch, the starter relay, and the ECU for shorts to power that might be sending a continuous crank signal to the ECU.

1. 1

   Disconnect Power

   Always disconnect the negative battery cable before working on the electrical system to prevent shorts.

2. 2

   Access the Switch

   Remove the necessary dash panel or operator control console covers to access the rear of the ignition switch.

3. 3

   Disconnect Wiring

   Pull the wiring harness connector off the back of the ignition switch. If the switch uses individual threaded screw terminals or posts, mark the wires before removing them to ensure correct reinstallation.

4. 4

   Remove the Old Switch

   Unscrew the retaining nut on the front side of the dash panel and pull the old switch out from the back.

5. 5

   Install the New Switch

   Insert the new ignition switch through the mounting hole in the dash and secure it tightly with the retaining nut.

6. 6

   Reconnect Wiring

   Reattach the wiring harness or individual wires to the correct terminals on the new switch.

7. 7

   Test

   Reconnect the battery. Turn the key to verify that the machine starts normally and that the starter disengages immediately when the key springs back to the "On" position.

8. 8

   Clear Codes

   Clear the F-1675-31 fault code from the ECU using a diagnostic tool or the machine's display monitor.