Massey Ferguson 13.01.18 – TRANS1: Brake System Pressure Not Dropped When Brake Applied Dyna VT

This fault indicates a hydraulic or sensor anomaly within the tractor's braking system. Specifically, when the operator applies the brake pedal, the system expects a corresponding drop in hydraulic pressure in a specific circuit (often related to the trailer brakes or cardan brake release). The controller detects that the pressure has remained too high, which can be caused by a sticking brake solenoid valve, a faulty pressure sensor, or a wiring issue.

• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S
• Tier 4 (2015-2021)
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 8660
• 8670
• 8680
• 8690
• 8727 S
• 8730 S
• 8732 S
• 8735 S
• 8737 S
• 8740 S
• 6713 S
• 6714 S
• 6715 S
• 6716 S
• 6718 S

1. 1

   Verify the code: Access the tractor's diagnostic interface to confirm 13.01.18 is active and not a stored historical code.

2. 2

   Perform a mechanical pressure check (Sensor vs. Mechanical): Plumb a manual hydraulic pressure gauge into the brake test port to verify actual physical pressure when the pedal is applied, determining if the sensor is reading incorrectly.

3. 3

   Inspect the brake pedal sensors: Check the left and right brake pedal position sensors/switches for proper voltage signals to ensure the TRANS1 module recognizes pedal position correctly.

4. 4

   Inspect wiring harness: Check the wiring connecting the TRANS1 module to the brake pressure sensor and brake solenoid valve for chafing, open circuits, or short circuits to ground.

5. 5

   Test the solenoid valve: Check the brake solenoid valve for sticking, as debris in the hydraulic oil can cause the spool to hang up and prevent pressure from exhausting.

1. 1

   Relieve Hydraulic Pressure

   Ensure the tractor is turned off, parked on a level surface, and the park brake is engaged. Pump the brake pedals several times to relieve residual hydraulic accumulator pressure.

2. 2

   Clean the Valve Block

   Locate the brake control valve block (often located under the cab or near the rear axle housing). Clean the area thoroughly to prevent dirt from entering the hydraulic system.

3. 3

   Replace the Faulty Component

   If the sensor is faulty: Unplug the electrical connector, unthread the old pressure sensor, install the new sensor, and reconnect the harness. If the solenoid valve is sticking: Remove the retaining bolts for the brake solenoid valve/cardan valve. Remove the valve, ensuring no O-rings are left behind in the manifold. Install the new valve with fresh, lubricated O-rings and torque to OEM specifications.

4. 4

   Bleed the Brakes

   If the hydraulic circuit was opened, bleed the brake system according to the service manual to remove any trapped air.

5. 5

   Clear Codes and Calibrate

   Connect the diagnostic tool, clear the 13.01.18 fault code, and perform a brake/transmission calibration routine to ensure the TRANS1 module learns the new component's parameters.

6. 6

   Test Drive

   Operate the tractor, apply the brakes firmly several times, and verify the code does not return.