Massey Ferguson 14.03.03 – TRANS1: High Pressure Brake System Pressure Too High DYNA 6 (TRANS1)

The tractor's electronic control system has detected that the hydraulic pressure within the high-pressure brake circuit has exceeded the maximum safe operating threshold. This can be caused by a failing brake pressure sensor sending an artificially high voltage signal, a short circuit in the sensor wiring, a stuck hydraulic pressure relief valve, or a restriction in the return line causing actual overpressure.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 5400
• 5600
• 5700 S/SL series
• 5611
• 5612
• 5613
• 5710
• 5711
• 5712
• 5713
• 6400
• 6600
• 6700 S series
• 6485
• 6490
• 6614
• 6615
• 6616
• 6713
• 6714
• 6715
• 6716
• 7600
• 7700 S series
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624

1. 1

   Verify Pedal Free Play: Ensure the brake pedals are fully returning to their resting position and have the correct free play (typically around 1 inch/25 mm). If the pedals are hanging up, they may be holding residual pressure in the system.

2. 2

   Inspect Wiring and Connectors: Locate the brake pressure sensor and inspect the wiring harness for chafing, corrosion, or a short-to-power, which would cause the ECU to read an artificially high pressure.

3. 3

   Compare Sensor vs. Mechanical Pressure: Use a diagnostic tool to read the live data from the brake pressure sensor. Connect a manual hydraulic pressure test gauge to the brake circuit test port. If the manual gauge reads normal pressure but the electronic sensor reads high, the sensor is faulty. If the manual gauge also reads too high, the issue is mechanical (e.g., a stuck relief valve).

4. 4

   Check Hydraulic Fluid: Ensure the transmission/hydraulic oil is at the correct level and the filters are not blocked, as restricted flow can cause pressure spikes.

1. 1

   Preparation

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and block the wheels.

2. 2

   Relieve Pressure

   Pump the brake pedals several times with the engine off to deplete any residual hydraulic pressure in the brake accumulators and lines.

3. 3

   Locate the Sensor

   Find the high-pressure brake sensor. Depending on the exact model, this is usually located near the brake master cylinders under the cab or on the transmission valve block.

4. 4

   Remove the Sensor

   Disconnect the electrical connector. Use a wrench to carefully unscrew the faulty pressure sensor. Have a rag ready to catch any minor fluid drips.

5. 5

   Install the New Sensor

   Thread the new OEM pressure sensor into the port and tighten to the manufacturer's torque specification. Reconnect the electrical harness.

6. 6

   Bleed the Brakes

   If air entered the system during the swap, bleed the brakes. Start the engine and let it idle. Open the bleed nipples on top of the rear axle trumpets one at a time while slowly depressing the corresponding brake pedal. Close the nipple once the fluid runs clear of air bubbles.

7. 7

   Clear Codes

   Use a diagnostic tool to clear the 14.03.03 fault code from the TRANS1 module and test drive the tractor to ensure the code does not return.