Massey Ferguson E12 – Transmission Control Unit (TCU): Clutch pedal potentiometer signal too high

High voltage reading from the clutch pedal potentiometer. On newer Global Series tractors, E12 may appear as a prefix with the actual fault code displayed below it.

• 4707
• 4708
• 4709
• 4710
• T4 (2015-2021)
• 5400 Series (5425, 5435, 5445, 5455, 5460, 5465, 5470, 5475, 5480)
• 6200 Series
• 6400 Series
• 6600 Series
• 7400 Series
• 7600 Series
• 8200 Series
• 8400 Series
• 8600 Series
• Global Series 4700/5700/6700

1. 1

   Inspect the clutch pedal potentiometer (located on the clutch pedal assembly in the cab) for physical damage, loose mounting, or debris.

2. 2

   Disconnect the sensor and inspect the electrical connector for corrosion, moisture, or bent pins. Check the wiring harness between the potentiometer and the Transmission Control Unit for shorts to power.

3. 3

   Use a multimeter to verify the 5V reference and ground circuits at the sensor connector. Test the potentiometer's resistance sweep while slowly depressing the pedal; if the resistance jumps erratically or shows an open/short circuit, the sensor has failed internally.

4. 4

   Attempt a clutch pedal calibration to see if the TCU can re-learn the sensor's parameters. If the calibration fails or the code immediately returns, the sensor must be replaced.

1. 1

   Safety First

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and disconnect the negative battery cable.

2. 2

   Locate the Sensor

   Locate the clutch pedal potentiometer attached to the pivot point of the clutch pedal assembly inside the cab.

3. 3

   Remove the Faulty Sensor

   Disconnect the electrical wiring harness from the potentiometer. Remove the mounting screws/bolts securing the sensor to the pedal bracket and slide the sensor off the pedal shaft.

4. 4

   Install the New Sensor

   Slide the new potentiometer onto the pedal shaft, ensuring the internal tangs align correctly with the pedal's pivot mechanism. Secure it with the mounting hardware.

5. 5

   Reconnect Wiring

   Plug the electrical connector back into the new sensor, ensuring it clicks into place. Reconnect the battery.

6. 6

   Perform Calibration

   Perform a Transmission / Clutch Pedal Calibration procedure so the TCU learns the new potentiometer's minimum (pedal up) and maximum (pedal down) voltage values.

7. 7

   Clear Codes and Test

   Clear the latched E12 fault code from the system. Test drive the tractor to verify smooth clutch engagement and ensure the code does not return.