Case IH 684-05 - VCM – VCM: Inching (clutch) pedal switch disagreement

This fault indicates a logic mismatch between the clutch pedal position sensor (potentiometer) and the Bottom of Clutch (BOC) pedal switch. Specifically, the fault is triggered when the BOC switch has not closed when the inching (clutch) pedal position is greater than 12% of its calibrated range, or the BOC switch has not opened when the inching pedal position is less than 2% of its calibrated range.

• MAGNUM AFS Connect
• Steiger
• Puma
• Maxxum

1. 1

   Check for a mechanically misadjusted or loose clutch pedal stop and ensure the pedal physically travels its full range without obstruction.

2. 2

   Verify that the Bottom of Clutch (BOC) switch is physically being depressed and released by the pedal arm.

3. 3

   Test the BOC switch for proper open/close continuity.

4. 4

   Test the clutch pedal position potentiometer for a smooth voltage sweep without dropouts.

5. 5

   Check the wiring harness between the pedal assembly and the VCM for voltage drops, voltage on ground wires, or shorts to ground.

1. 1

   Adjust the Pedal Stop / Switch

   If the pedal stop is loose or the switch is misadjusted, mechanically adjust the BOC switch so that it correctly opens and closes at the very bottom of the pedal travel.

2. 2

   Replace Faulty Components

   If the switch fails the continuity test or the potentiometer has a dead spot in its voltage sweep, replace the faulty component.

3. 3

   Calibrate the Inching Pedal

   After adjusting or replacing the switch/sensor, you must perform an inching pedal calibration (often referred to as a clutch fill time calibration or pedal calibration) via the tractor's display monitor or a diagnostic service tool. The VCM needs to relearn the 0% to 100% travel limits.

4. 4

   Clear Codes

   Clear the 684-05 fault code from the VCM and test drive the tractor to ensure smooth forward/reverse modulation and that the code does not return.