Massey Ferguson A.42.26 – Onboard diagnostic system: External Hydraulic Valve 4 Issue

Indicates a potential issue or fault with the 4th external hydraulic remote/spool valve. It often points to a connection problem on the hydraulic valve, restricted oil flow, or a mechanical failure within the valve itself.

• 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 and connector at External Valve 4 for corrosion, damage, or loose pins (connection problem)

2. 2

   Check the hydraulic oil filter or transmission filter for contamination or blockages (restricted oil flow)

3. 3

   Inspect the hydraulic couplers and hoses for damage or blockages

4. 4

   Check for sticky valves or worn spool valve detents, especially on 7600 series models (mechanical failure)

1. 1

   Address Basic Service Items

   If the hydraulic fluid is dirty or filters are clogged, drain the fluid, replace the hydraulic/transmission filters, and refill with clean, manufacturer-approved hydraulic oil.

2. 2

   Repair Wiring

   If the diagnostic check revealed a wiring fault at Valve 4, repair or replace the damaged connector/harness.

3. 3

   Repair or Replace the Valve

   If the issue is mechanical wear in the detents (common on 7600 series), modify and install a replacement detent kit. If the valve has suffered a complete internal failure or electrical solenoid failure, replace the entire spool valve assembly.

4. 4

   Software Calibration

   Once a spool valve is replaced with a new one, use a compatible diagnostic tool (such as Jaltest AGV or the Massey Ferguson dealer tool) to assign the new valve the position of the one that was replaced.

5. 5

   Clear Codes

   Clear the DTCs from the system and test the hydraulic remote for proper operation.