Massey Ferguson A.4X.22 – Onboard Diagnostic System / Main Tractor ECU: External Hydraulic Valve 4 Issue

Malfunction, electrical short, or communication failure with the 4th rear hydraulic remote valve (spool valve).

• 5710SL
• 5711SL
• 5712SL
• 5713SL
• T4
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626
• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S

1. 1

   Inspect the wiring harness leading to the rear hydraulic remote stack (specifically the 4th valve) for chafing, rodent damage, or pinched wires.

2. 2

   Disconnect the electrical plug at External Valve 4 and inspect for water ingress, bent pins, or corrosion.

3. 3

   Perform a swap test: temporarily swap the electrical connection from Valve 4 to Valve 3. If the fault code changes to an 'External Hydraulic Valve 3 Issue', the spool valve slice itself is faulty. If the code remains on Valve 4, the issue is in the tractor's wiring harness or ECU.

1. 1

   Power Down

   Turn off the tractor and disconnect the negative battery terminal to prevent short circuits.

2. 2

   Relieve Pressure

   Relieve all hydraulic pressure from the rear remotes by cycling the manual release levers or ensuring implements are lowered.

3. 3

   Clean the Area

   Thoroughly clean the rear remote valve stack to prevent dirt from entering the hydraulic system.

4. 4

   Remove the Faulty Slice

   Disconnect the electrical harness from Valve 4. Unbolt the tie-rods holding the hydraulic valve stack together. Carefully slide out the faulty electric spool slice, ensuring you do not lose the O-rings between the slices.

5. 5

   Install the New Valve

   Insert the replacement electric spool slice with new O-rings. Re-torque the stack tie-rods to OEM specifications.

6. 6

   Reconnect and Calibrate

   Reconnect the electrical harness. Reconnect the battery. Note: New electric spool slices often need to be programmed/calibrated to the tractor's ECU using a compatible Massey Ferguson diagnostic tool before they will function correctly.

7. 7

   Clear Codes

   Use the diagnostic tool to clear the 0A.4X.22 code and test the remote for proper operation.