Case IH 684-06 - VCM – VCM: Inching (clutch) pedal switch disagreement

The control module is receiving an erratic, out-of-range, or conflicting signal from the inching/clutch pedal switch or potentiometer. This means the physical position of the pedal does not match the electrical state expected by the controller, which can cause the tractor to refuse to move, drop out of gear, or exhibit harsh/jerky clutch engagement.

• MAGNUM AFS Connect
• Case IH Magnum Series (MX210, MX230, MX255, MX285, 235, 275, 340, AFS Connect)
• Case IH Maxxum Series (5120-5250, 110, 115, 120, 125, 130, 140, 150)
• Case IH Puma Series
• Case IH Farmall Series (95U, 105U, 115U)
• Case IH Steiger / STX Series

1. 1

   Visually and mechanically inspect the clutch pedal assembly. Ensure the pedal returns fully to the top of its stroke and that the switch/potentiometer bracket is not bent or loose.

2. 2

   Disconnect the switch harness. Turn the key to the ON position and use a multimeter to verify the reference voltage at the connector (5V or 8V).

3. 3

   Test the switch itself for continuity (if a 4-terminal switch, verify it opens and closes as the plunger is depressed) or test the potentiometer for a smooth resistance sweep without dead spots.

4. 4

   Check the harness routing down to the VCM for chafing, short circuits to ground, or open circuits.

5. 5

   Attempt a 'Cal Pedal' (Clutch Pedal Calibration) procedure through the tractor's display menu before buying parts, as the VCM may have simply lost the pedal's learned parameters.

1. 1

   Access the Switch

   Locate the inching pedal switch/potentiometer at the base of the clutch pedal pivot assembly inside the cab.

2. 2

   Removal

   Disconnect the electrical connector. Remove the mounting hardware (typically M5 or M6 metric nuts/bolts) and slide the faulty switch out of its bracket.

3. 3

   Installation

   Install the new switch and tighten the mounting hardware. Reconnect the wiring harness.

4. 4

   Mechanical Adjustment

   Adjust the switch physically (if threaded) so that the plunger is correctly depressed when the pedal is at rest, but does not bottom out and bind when the pedal is fully depressed.

5. 5

   Electronic Calibration

   Warm the tractor up until the transmission oil temperature is above 50°C (122°F). Enter the tractor's H-Menu or Program menu, navigate to Trans Menu -> Trans Setup -> Calibrate Clutch Pedal (or 'Cal Pedal'), follow the on-screen prompts to register the 'Pedal Up' and 'Pedal Down' positions, save the calibration, and cycle the ignition key.