Massey Ferguson 14.00.07 – TRANS1: Brake Pressure Sensor Open Circuit

The transmission controller is not receiving a valid electrical signal from the high-pressure brake system sensor (ParkLock brake pressure sensor or trailer brake pressure sensor), indicating an open circuit typically caused by a disconnected sensor plug, a severed wire in the harness, or a completely failed internal circuit within the sensor itself.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 5709 S
• 5710 S
• 5711 S
• 5712 S
• 5713 S
• 6713 S
• 6714 S
• 6715 S
• 6716 S
• 6718 S
• 7715 S
• 7716 S
• 7718 S
• 7720 S
• 7722 S
• 7724 S
• 7726 S
• MF 7000 Series
• MF 7600 Series
• MF 8600 Series

1. 1

   Locate the brake pressure sensor (designated as X21 or TR44) on the transmission/brake valve block

2. 2

   Visually inspect the sensor connector to ensure it is fully seated and locked, as a disconnected sensor is the primary cause for this fault

3. 3

   Inspect the wiring harness between the sensor and the TRANS1 controller for chafed wires, corrosion, or broken pins

4. 4

   Use a multimeter to verify continuity on the signal, ground, and reference voltage wires

5. 5

   Verify that the sensor is receiving its standard reference voltage (typically 5V) from the controller

1. 1

   Safety First

   Park the tractor on level ground, turn off the engine, engage the parking brake (if mechanically possible), and relieve any residual hydraulic/pneumatic pressure in the brake system.

2. 2

   Clean the Area

   Thoroughly clean the area around the brake pressure sensor (X21/TR44) to prevent dirt from entering the hydraulic system.

3. 3

   Disconnect Wiring

   Unplug the electrical connector from the sensor. If the diagnostic checks revealed a broken wire or corroded pin, repair the harness using an appropriate OEM pigtail or pin replacement kit.

4. 4

   Remove the Sensor

   If the sensor is faulty, use a wrench to unthread the sensor from the valve block. Have a shop towel ready to catch minor fluid drips.

5. 5

   Install the New Sensor

   Thread the new OEM brake pressure sensor into the port. Tighten it to the torque specification outlined in your specific model's service manual.

6. 6

   Reconnect and Test

   Reconnect the electrical harness. Turn the tractor's ignition on and test the brake/ParkLock operation.

7. 7

   Clear Codes

   Connect a diagnostic tool (such as the AGCO Electronic Diagnostic Tool) to the tractor and clear the 14.00.07 fault code from the TRANS1 (Autotronic 5) module.