Case IH 91-03 - VCM – VCM: Foot Pedal Position Sensor Signal Voltage High

The signal voltage from the foot pedal position sensor (accelerator pedal) is exceeding the normal operating range. This usually points to a short to power in the signal wire, an open/broken ground circuit, or an internal short within the sensor itself.

• MAGNUM AFS Connect
• Magnum
• Steiger
• Puma
• Maxxum
• SV185
• SV250
• TR320
• Axial-Flow Combines

1. 1

   Inspect the wiring harness and connector at the foot pedal for physical damage, chafing, or corrosion.

2. 2

   Disconnect the sensor with the key ON (engine off) and measure the reference voltage pin on the harness side to ensure it reads a steady 5V (or 8V).

3. 3

   Verify continuity to ground on the sensor ground pin to check for an open ground.

4. 4

   Test the signal wire for a short to battery voltage.

5. 5

   If the reference voltage, ground, and signal wire are good, the sensor has failed internally and must be replaced.

1. 1

   Power Down

   Turn off the machine, remove the key, and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Access the Pedal

   Locate the foot pedal position sensor assembly on the cab floor. Remove any floor mats or trim panels obstructing the mounting hardware.

3. 3

   Disconnect

   Unplug the electrical harness connector from the pedal sensor.

4. 4

   Remove

   Unbolt the mounting hardware securing the pedal assembly or sensor to the floor bracket.

5. 5

   Install

   Mount the new sensor/pedal assembly and torque the bolts to OEM spec.

6. 6

   Reconnect

   Plug in the electrical connector and reconnect the battery.

7. 7

   Calibrate

   Turn the key ON and perform a 'Foot Pedal Calibration' using the tractor's display monitor (e.g., AFS Pro 700 / Pro 1200) or an electronic service tool to teach the VCM the new minimum and maximum voltage values.