Massey Ferguson A.2X.21 – Auxiliary Valve Controller / Hydraulic ECU: External Hydraulic Valve 2 Issue

Malfunction, connection problem, or spool position sensor error on the second external hydraulic remote valve. The system has detected that the valve is either not responding correctly to commands, has a wiring fault, or the spool is failing to return to the neutral position.

• 5710SL
• 5711SL
• 5712SL
• 5713SL
• T4
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7714
• 7715
• 7716
• 7718
• 7719
• 7720
• 7722
• 7724
• 7726

1. 1

   Check hydraulic fluid and filters for contamination or blockages that can restrict flow and cause valves to stick or perform weakly

2. 2

   Inspect electrical connections, wiring harness, and the connector plugging into External Hydraulic Valve 2 for corrosion, broken wires, or loose pins

3. 3

   Check for mechanical binding by inspecting spool valve detents and linkages for rust or accumulated debris that prevents the spool from returning to neutral

4. 4

   Verify the spool position sensor using a dealer diagnostic tool to read live values and ensure it reads correctly and returns to neutral

1. 1

   Relieve Pressure

   Lower all implements to the ground, turn off the tractor, and actuate the hydraulic levers to relieve any residual hydraulic pressure in the system.

2. 2

   Locate the Valve

   Locate the External Hydraulic Valve 2 on the rear remote valve stack (or front axle block, depending on the tractor's configuration).

3. 3

   Clean and Inspect

   Disconnect the electrical harness. Clean the contacts with electrical contact cleaner. Inspect the mechanical detents; if they are rusted, clean and lubricate them.

4. 4

   Replace the Spool Slice

   If the electrical solenoid or internal position sensor has failed, the electric spool slice must be replaced. Remove the retaining bolts holding the valve stack together and carefully slide the faulty spool slice out.

5. 5

   Install New Valve

   Insert the new electric spool slice, ensuring all O-rings are properly seated to prevent internal pressure loss. Torque the retaining bolts to factory specifications.

6. 6

   Programming

   A new electric spool slice must be programmed/calibrated to the tractor's ECU using a compatible diagnostic tool so the system recognizes the new valve's parameters.

7. 7

   Test

   Top up the hydraulic fluid, start the tractor, and test the remote valve for proper operation, ensuring there are no leaks and the fault code clears.