Massey Ferguson A.40.20: External Hydraulic Valve 4 Issue

The tractor's onboard diagnostic system has detected a fault in the circuit or operation of the 4th external auxiliary hydraulic remote valve. This is typically an electrical or connection problem, such as a solenoid circuit being open, shorted to ground, or shorted to power, or a signal that is out of range.

• 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 electrical circuit and wiring harness leading to the External Hydraulic Valve 4 solenoid for rub points, open circuits, or shorts.

2. 2

   Test the solenoid coil resistance and verify ground integrity.

3. 3

   Check the hydraulic fluid (UTTO) level and condition, looking for dark, burnt, or milky fluid indicating water contamination.

4. 4

   Inspect the hydraulic filter for partial blockages that could restrict flow to the system.

5. 5

   Perform a system pressure test with a hydraulic gauge to determine if the issue is isolated to the valve itself or if there is a broader pump/relief valve restriction.

6. 6

   Check the control unit dashboard to see if the system has placed the valves into a blocked or locked-out state due to the error code.

1. 1

   Resolve Wiring/Electrical Faults

   If the diagnostic checks reveal a short or open circuit, repair the damaged wiring harness or replace the faulty solenoid valve coil on Valve 4.

2. 2

   Unstick the Valve

   If the valve spool is mechanically bound, manually move the pump control valve lever back and forth to attempt to release it.

3. 3

   Fluid and Filter Maintenance

   If the hydraulic fluid is degraded or contaminated, drain the system, flush it, and refill with fresh UTTO fluid. Replace the hydraulic filter.

4. 4

   Valve Replacement/Rebuild

   If the valve has failed internally, remove the valve block and either rebuild or replace it.

5. 5

   Clear Codes and Unlock

   Once the physical repair is made, use a compatible diagnostic tool or the dashboard interface to delete the error code from the control unit and unlock the hydraulic valves to restore functionality.