Massey Ferguson 04.01.22 – TRANS: Issue With Signal Voltage From Foot Throttle Sensor (TRANS)

The controller is receiving an implausible voltage signal from the foot throttle sensor (potentiometer) that falls outside the expected operating range. Specifically, the voltage read by the controller is either greater than 4.5V (maximum) or lower than 0.5V (minimum). When this occurs, the system will typically inhibit the throttle, default to a limited RPM mode, or refuse to respond to throttle input to protect the engine and transmission.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613

1. 1

   Voltage Sweep Test: Use a multimeter or diagnostic tool to monitor the sensor's voltage output while slowly pressing the foot pedal. The voltage should smoothly sweep between 0.5V and 4.5V. If there are dead spots, or if the voltage spikes above 4.5V or drops below 0.5V, the sensor is faulty.

2. 2

   Wiring & Connector Inspection: Check the wiring harness between the foot throttle sensor and the Transmission Control Unit (TCU). Look for open circuits, shorts to ground, or shorts to power.

3. 3

   Reference Voltage Check: Disconnect the sensor and verify that the connector is receiving a steady 5V reference and a solid ground from the controller.

4. 4

   Physical Inspection: Ensure there is no physical debris blocking the pedal's travel, and check the connector for moisture, corrosion, or pushed-out pins.

1. 1

   Preparation

   Turn off the tractor, apply the handbrake, set the PowerShuttle lever to neutral, and ensure the PTO is disengaged.

2. 2

   Access the Sensor

   Locate the foot throttle sensor/potentiometer assembly at the base of the throttle pedal inside the cab.

3. 3

   Removal

   Disconnect the electrical connector from the sensor. Remove the mounting bolts securing the potentiometer to the pedal assembly.

4. 4

   Installation

   Mount the new throttle potentiometer and secure the hardware. Reconnect the electrical connector.

5. 5

   Calibration (Crucial Step)

   According to OEM service guidelines, the throttle pedal potentiometer must be recalibrated every time the sensor is replaced or modified. Connect the AGCO Electronic Diagnostic Tool (EDT) or use the tractor's onboard diagnostic screen (if equipped) to run the throttle calibration procedure. This allows the TCU to learn the new 0% (idle) and 100% (full throttle) voltage limits.

6. 6

   Clear Codes

   Clear the 04.01.22 fault code from the transmission controller and test drive the tractor to verify normal throttle response.