Massey Ferguson 04.02.20 – TRANS (Transmission Control Module / TCU): Issue With Signal Voltage From Foot Throttle Sensor

The controller is receiving an electrical signal from the foot throttle (accelerator pedal) that falls outside the acceptable parameters (greater than 4.5V or lower than 0.5V). When this occurs, the tractor may default to a limited RPM mode, inhibit throttle requests, or refuse to respond to the foot pedal entirely as a safety precaution.

• 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

   Inspect the wiring harness leading to the foot throttle sensor for any obvious signs of chafing, broken wires, or melted insulation.

2. 2

   Disconnect the sensor and check the pins for corrosion, moisture, or bent terminals.

3. 3

   Using a multimeter, probe the sensor's signal wire while the key is ON (engine off) to verify if the voltage is stuck outside the normal 0.5V to 4.5V operating range.

4. 4

   Check for a short circuit to ground or a short circuit to the power supply within the accelerator pedal wiring.

1. 1

   Power Down

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

2. 2

   Access the Sensor

   Locate the foot throttle sensor potentiometer, which is mounted directly to the accelerator pedal assembly inside the cab.

3. 3

   Harness Repair (If Applicable)

   If the diagnostic checks revealed a broken wire or short circuit in the harness, splice and repair the damaged section using weatherproof heat-shrink connectors.

4. 4

   Replace the Sensor

   If the wiring is intact but the sensor failed the voltage test, disconnect the electrical plug from the sensor. Unbolt the sensor/pedal assembly from the floorboard mounting bracket.

5. 5

   Install New Part

   Bolt the new foot throttle sensor into place and reconnect the electrical harness.

6. 6

   Reassemble and Clear Codes

   Reconnect the battery. Turn the key on and use the tractor's diagnostic interface (or a dealer tool) to clear the inactive 04.02.20 fault code.

7. 7

   Calibration

   Test the pedal. Depending on the Datatronic monitor software version, you may need to navigate to the transmission settings to verify throttle response and acceleration sensitivity.