Case IH 3375 – Engine Controller (ENG) / Engine ECU: Constant engine RPM increase / decrease switch - short circuit to battery

The system is detecting that the electrical circuit for the switch used to set, increase, or decrease the constant engine speed is receiving unintended continuous battery voltage (a short to power), preventing the system from reading the switch's actual inputs.

• Magnum Series
• Steiger Series
• Puma Series
• Maxxum Series
• Farmall Series

1. 1

   Visually inspect the Constant Engine RPM switch for physical damage, sticking buttons, or liquid intrusion.

2. 2

   Disconnect the switch and test the signal wire in the harness for continuity to battery voltage (12V) to check for a short to power.

3. 3

   Test the switch for internal short circuits by checking for continuity across the terminals without pressing the buttons.

1. 1

   Disconnect Power

   Disconnect the tractor's battery to prevent electrical damage or accidental shorts during the repair.

2. 2

   Access the Switch

   Remove the necessary trim panels on the armrest, multicontroller, or side console to access the back of the Constant Engine RPM switch.

3. 3

   Disconnect the Component

   Unplug the electrical connector from the switch.

4. 4

   Address the Short

   If the harness is shorted: Trace the wiring harness back to the Engine ECU. Locate the chafed or melted section of the wire that is contacting a 12V power source. Repair the wire and insulate it, or replace that section of the harness. If the switch is shorted: Remove the retaining clips or screws holding the faulty switch in place and remove it from the console.

5. 5

   Install New Parts

   Snap or screw the new Constant Engine RPM switch into the console and reconnect the electrical connector.

6. 6

   Reassemble

   Reinstall all armrest or console trim panels.

7. 7

   Test

   Reconnect the battery. Start the tractor and test the constant engine RPM function (setting and adjusting the RPMs). Verify via the instrument cluster or diagnostic tool that fault code 3375 has moved to an inactive state or cleared.