Massey Ferguson 00.1.39 – Dash: Issue With Signal Voltage From Clutch Pedal Sensor, High Voltage

The control module is receiving a voltage signal from the clutch pedal position sensor (potentiometer) that exceeds the expected maximum threshold (typically above 4.5V). This condition is usually caused by a short circuit to power (+12V or +5V reference), a broken ground wire, or an internal failure of the sensor itself.

• 5710SL
• 5711SL
• 5712SL
• 5713SL
• T4
• 7714
• 7715
• 7716
• 7718
• 7719
• 7720
• 7722
• 7724
• 7726
• 7700 Series
• 7700S Series
• 4700 Series
• 5700 Series
• 6700 Series
• 7600 Series
• 5400 Series
• 6400 Series
• 7400 Series

1. 1

   Inspect the wiring harness and connector at the clutch pedal sensor (located in the cab pedal box) for chafing, pinched wires, or corrosion that could cause a short to power or an open ground.

2. 2

   Perform a voltage sweep test by back-probing the sensor connector with a multimeter. The signal voltage should sweep smoothly between 0.5V and 4.5V as the pedal is depressed and released. If stuck at a high value (e.g., 5V or 12V), the sensor is internally shorted or there is a wiring fault.

3. 3

   Inspect the physical linkage and the clutch pedal sensor fork for damage, binding, or a disconnected linkage that might push the sensor past its normal operating range.

4. 4

   Verify the 'Bottom of Clutch Switch' is functioning correctly, as it works in tandem with the position sensor to verify pedal travel.

1. 1

   Disconnect Power

   Turn off the tractor ignition and disconnect the negative battery terminal to prevent electrical spikes.

2. 2

   Access the Sensor

   Locate the clutch pedal sensor (potentiometer) on the side of the clutch pedal assembly inside the cab.

3. 3

   Remove the Faulty Sensor

   Disconnect the electrical connector from the sensor. Remove the mounting screws/hardware securing the sensor and the sensor fork to the pedal assembly.

4. 4

   Install the New Sensor

   Mount the replacement clutch pedal sensor and ensure the mechanical linkage/fork is properly aligned with the pedal pivot. Secure the mounting hardware.

5. 5

   Reconnect

   Plug the electrical connector back into the sensor and reconnect the battery.

6. 6

   Clear Codes and Calibrate

   Turn the ignition on. Clear the inactive 00.1.39 fault code from the Dash display.

7. 7

   Clutch Calibration

   You must perform a clutch pedal calibration (often done via the dash menu or using Wintest diagnostic software) to teach the controller the new minimum and maximum voltage values for the pedal's travel.