Massey Ferguson 14.X.09 – TRANS1: High Pressure Brake System Pressure Too Low

The hydraulic pressure within the tractor's braking circuit has dropped below the minimum safe operating threshold, which can lead to a spongy brake pedal, poor braking performance, or a complete loss of braking assist.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 5400 Series
• 5600 Series
• 5700 S / SL Series
• 6400 Series
• 6700 S Series
• 7600 Series
• 7700 S Series

1. 1

   Verify transmission/hydraulic fluid reservoir is at the correct level, as low fluid will starve the brake pump

2. 2

   Inspect the brake pressure sensor and its wiring harness for frayed wires, corrosion at the connector, or signs of an open/short circuit

3. 3

   Test the brake accumulator for loss of nitrogen pre-charge, which causes rapid pressure drop when brakes are applied

4. 4

   Check brake lines, pneumatic/hydraulic brake solenoid valves, and brake master cylinders for external or internal hydraulic leaks

1. 1

   Top Up Fluids

   If the hydraulic fluid is low, fill it to the OEM specified level and test the tractor to see if the code clears.

2. 2

   Replace the Sensor

   If diagnostics point to a faulty sensor providing erratic or falsely low readings to the TRANS1 module, depressurize the system, unscrew the old sensor, and install the new one.

3. 3

   Replace the Accumulator

   If the system loses pressure immediately upon braking (or if the accumulator fails a pressure test), safely relieve all hydraulic pressure from the brake circuit, unbolt the old accumulator, and install a new pre-charged unit.

4. 4

   Bleed the Brakes

   Any time the hydraulic brake circuit is opened (whether replacing the sensor, accumulator, or lines), you must bleed the brake system to remove trapped air.

5. 5

   Clear Codes

   Use a diagnostic tool to clear the 14.X.09 code from the TRANS1 module and test drive the tractor to ensure consistent brake pedal feel and pressure.