Massey Ferguson 13.02.2D – TRANS1: Brake System Pressure Signal Issue Dyna VT (TRANS1)

The transmission control system is receiving an abnormal, missing, or out-of-range electrical signal from the brake system pressure sensor. This sensor monitors the pneumatic air supply or hydraulic pressure feeding the tractor's braking system (often the trailer brakes or the handbrake/park brake assembly). When the signal fails, the tractor's control system cannot accurately verify if the brakes have the proper pressure to function safely.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 6614
• 6615
• 6616
• 6713 S
• 6714 S
• 6715 S
• 6716 S
• 6718 S
• 7619
• 7620
• 7622
• 7624
• 7715 S
• 7716 S
• 7718 S
• 7719 S
• 7720 S
• 7722 S
• 7724 S
• 7726 S
• 8660
• 8727 S
• 8730 S
• 8732 S
• 8735 S
• 8737 S
• 8740 S

1. 1

   Wiring and Connector Inspection: Because this is a "Signal Issue," first check the electrical harness and connector at the brake pressure sensor for corrosion, moisture, rubbed wires, or loose pins.

2. 2

   Verify Physical Pressure: Ensure the issue is actually electrical and not a genuine mechanical pressure failure. Check the air lines for blockages or leaks.

3. 3

   Inspect the Park Brake Assembly: Look at the assembly under the cab on top of the transmission. There is a hydraulic cylinder that controls the brake pods for the park brake; verify that low physical pressure isn't mechanically triggering the fault.

4. 4

   Check for Contamination: Contaminated air systems (debris or moisture in the lines) can cause premature sensor failure. Ensure the air supply lines are clean.

1. 1

   Secure the Machine

   Park the tractor on a level surface, engage the park brake, and turn off the engine.

2. 2

   Locate the Sensor

   Locate the faulty brake pressure sensor. Depending on your exact configuration, it will be threaded into the pneumatic air supply line (for trailer brakes) or the hydraulic brake block (for the handbrake).

3. 3

   Relieve Pressure

   If removing a pneumatic sensor, ensure the air system is safely drained of pressure before unthreading the component.

4. 4

   Remove the Sensor

   Disconnect the electrical harness. Unscrew the sensor from the port.

5. 5

   Clean the Port

   Ensure the threads and the line are completely free of dirt and debris. Do not let contaminants fall into the brake lines.

6. 6

   Install the New Sensor

   Thread the direct-replacement OEM sensor into the port and tighten it to the manufacturer's specification. No adapters should be needed.

7. 7

   Reconnect and Test

   Plug the electrical connector back in. Start the tractor, allow the system to build pressure, and test the brake function at a low speed to ensure the code clears and performance is restored.