Massey Ferguson 14.X.01 – TRANS1: High Pressure Brake System Pressure Too Low

The pressure in the tractor's pneumatic/hydraulic braking system has dropped below the safe operating threshold (lower than 4 bar or 58 psi). When this occurs, the pneumatic brake pressure indicator light will illuminate on the dash, and transmission functions (like the ParkLock) may be restricted.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 5611
• 5612
• 5613
• 5709
• 5710
• 5711
• 5712
• 5713
• 6465
• 6475
• 6480
• 6485
• 6490
• 6495
• 6497
• 6499
• 6614
• 6615
• 6616
• 6713
• 6714
• 6715
• 6716
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 8670
• 8680
• 8690
• 8727
• 8730
• 8732
• 8735

1. 1

   Check implement connections and air connection couplers for massive air leaks at the trailer/implement brakes (primary cause of low pressure).

2. 2

   Inspect the tractor's pneumatic braking system lines, accumulator, and fittings for audible air leaks or physical damage.

3. 3

   Verify actual system pressure using a manual pressure gauge to confirm if it is dropping below 4 bar (58 psi).

4. 4

   Test the braking pressure sensor (Handbrake/Trailer Brake Pressure Sensor) for a false low-voltage signal if the system holds adequate pressure.

1. 1

   Depressurize the System

   Safely park the tractor on level ground. Turn off the engine and pump the brakes to deplete the stored pressure in the pneumatic/hydraulic brake accumulator to prevent injury.

2. 2

   Locate the Sensor

   Locate the high-pressure brake sensor, which is typically threaded into the brake valve assembly or near the brake accumulator depending on the specific model series.

3. 3

   Disconnect Wiring

   Carefully unplug the electrical harness connector from the sensor. Inspect the harness for corrosion, broken wires, or moisture, cleaning it with contact cleaner if necessary.

4. 4

   Remove the Sensor

   Using the appropriate wrench, unthread the faulty pressure sensor from the port.

5. 5

   Install the New Sensor

   Thread the new OEM pressure sensor into the port. Tighten to the torque specification outlined in your specific model's service manual (do not overtighten, as this can damage the brass/aluminum threads).

6. 6

   Reconnect and Test

   Reconnect the electrical harness. Start the tractor and allow the compressor/pump to build system pressure. Verify that the dash warning light goes out and the 14.X.01 fault code clears.