Massey Ferguson 14.02.06 – TRANS1: High Pressure Brake System Charging Too Often DYNA 6 (TRANS1)

The tractor's control system detects that the hydraulic pump is being commanded to recharge the high-pressure brake circuit much more frequently than normal. This can be caused by the accumulator losing its gas charge, an internal hydraulic leak in the brake circuit, or a faulty brake pressure sensor giving erratic readings.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 5400 Series
• 5465
• 5600 Series
• 5611
• 5612
• 5613
• 5700 Series
• 5700 S Series
• 5700 SL Series
• 5710
• 5711
• 5712
• 5713
• 6400 Series
• 6485
• 6490
• 6495
• 6700 S Series
• 6713
• 6714
• 6715
• 6716
• 6718
• 7600 Series
• 7614
• 7615
• 7618
• 7620
• 7624
• 7700 Series
• 7700 S Series

1. 1

   Test the brake accumulator (most common cause): Connect a hydraulic pressure gauge to the brake circuit test port. If pressure drops instantly when the brake pedal is pressed and the pump immediately kicks in, the accumulator has lost its nitrogen pre-charge.

2. 2

   Inspect brake lines, accumulator threads, and the brake valve block for visible external hydraulic fluid leaks.

3. 3

   Check for internal leaks at the brake piston seals or trailer brake valve if no external leaks are found.

4. 4

   Verify the brake pressure sensor: Use a diagnostic scan tool to monitor live data. Erratic or artificially low voltage readings indicate a faulty sensor causing the pump to over-cycle.

1. 1

   Depressurize the System

   Turn off the tractor engine. Pump the brake pedals repeatedly (usually 20 to 30 times) until the pedals feel completely stiff. This ensures all residual hydraulic pressure stored in the accumulator is released.

2. 2

   Locate the Accumulator

   Find the high-pressure brake accumulator, which is typically a spherical metal canister mounted near the transmission housing or brake valve block.

3. 3

   Clean the Area

   Thoroughly clean the area around the accumulator base to prevent dirt from entering the hydraulic system when the component is removed.

4. 4

   Remove the Accumulator

   Carefully unscrew the accumulator from the valve block. Have a shop rag ready to catch minor fluid drips.

5. 5

   Install the New Accumulator

   Lubricate the new O-ring/seal with clean hydraulic oil. Thread the new accumulator into place and tighten it to the manufacturer's specified torque.

6. 6

   Bleed the Brakes

   Start the tractor and allow the hydraulic system to charge the new accumulator. Bleed the brake system at the rear axles according to the service manual to remove any trapped air.

7. 7

   Clear Codes and Test

   Use a diagnostic tool to clear fault code 14.02.06. Test drive the tractor, applying the brakes repeatedly to ensure the pump cycles normally and the code does not return.