Massey Ferguson D142 – Dashboard / Instrument Panel (Dash): Issue With Signal Voltage From Clutch Pedal Sensor, High Voltage

Short circuit to +12 V AC on the X68 Clutch Pedal Sensor (Top-of-Clutch or TOC switch). The controller is receiving a maximum voltage signal indicating a short in the circuit rather than the expected variable or switched voltage from normal pedal operation.

• MF 8650
• MF 8680
• Interim Tier 4 (2012-2015)
• 7615
• 5613
• MF 8480
• MF 8450
• 7616
• 7618
• 5608
• 7619
• 7626
• MF 8660
• 7624
• MF 8690
• 7614
• MF 8470
• 5610
• 7620
• MF 8600
• MF 8460
• MF 8670
• 5612
• 7622
• 5611
• 5609
• 5400 Series
• 6400 Series
• 7400 Series
• 8400 Series
• 7600 Series (7614-7626)
• 7700 / 7700S Series (7714-7726 Tier 4 models)
• 8600 Series (8670, 8690)

1. 1

   Inspect the X68 Top-of-Clutch (TOC) switch in the pedal box to see if it is physically defective, stuck, or wrongly adjusted.

2. 2

   Test the wiring harness connected to the X68 sensor for a direct short circuit to a +12V power source.

3. 3

   Check the continuity of the CAN network wires (CAN High and CAN Low) between the DCC controller and the Autotronic transmission controller, ensuring they are not shorted to 12V.

1. 1

   Access the Pedal Box

   Locate the clutch pedal sensor assembly (X68) situated in the clutch pedal box inside the cab.

2. 2

   Test and Repair Wiring

   Disconnect the sensor and use a multimeter to verify if the short to +12V is in the tractor's wiring harness. If a short is found, repair the damaged wire.

3. 3

   Replace the Sensor

   If the wiring is intact, the sensor itself has failed internally. Remove the retaining hardware and extract the faulty Top-of-Clutch / Clutch Pedal sensor.

4. 4

   Install the New Sensor

   Fit the replacement sensor, ensuring it is properly aligned with the pedal's resting position so it is not permanently held open or closed.

5. 5

   Calibrate the Clutch

   After replacing pedal switches or potentiometers, you must perform a clutch pedal calibration (often done via the dashboard sequence or diagnostic software) so the transmission controller can relearn the engagement and disengagement points.

6. 6

   Clear Codes

   Clear the D142 fault code from the dashboard memory and cycle the key to confirm the repair.