Massey Ferguson 0A.21.1A – Hydraulic implement control module: External Hydraulic Valve 2 Issue

Indicates a fault associated with the second external hydraulic remote valve (spool valve 2). The underlying condition is typically an electrical connection problem on the hydraulic valve, an issue with the spool position sensor value, or a mechanical issue such as the valve sticking/jamming due to internal wear or debris.

• 7724S
• 5712SL
• 7722
• 7722S
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7726S
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 4707
• 4708
• 4709
• 4710
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7614
• 7615
• 7616
• 7618
• 7619
• 7620
• 7622
• 7624
• 7626

1. 1

   Verify the hydraulic fluid (UTTO) level and condition, looking for dirty oil or blocked hydraulic/transmission filters which can cause valves to stick

2. 2

   Inspect the wiring harness and electrical connector at External Hydraulic Valve 2 (located in the rear remote stack) for corrosion, loose pins, or damaged wires

3. 3

   Use a compatible diagnostic tool to check the spool position sensor values and verify communication between the dash and the valve module

4. 4

   Test if the valve is physically sticking or jamming due to debris or internal wear

1. 1

   Depressurize the System

   Turn off the tractor and relieve all hydraulic system pressure by cycling the hydraulic controls.

2. 2

   Inspect and Clean Connections

   Locate External Hydraulic Valve 2. Disconnect the electrical connector. Clean the contacts with electrical contact cleaner and reconnect. If the wiring is damaged, repair the harness.

3. 3

   Remove the Valve

   If the electrical connection is sound but the code persists, the spool valve slice itself is likely faulty. Unbolt the hydraulic lines and remove the valve slice from the stack.

4. 4

   Rebuild or Replace

   Depending on the severity of the wear, either rebuild the valve using an OEM repair kit (replacing seals and worn internal components) or replace the entire electric spool slice. Note: Some new electric spool slices require programming to the tractor upon installation.

5. 5

   Reassemble and Refill

   Reinstall the valve, reconnect the hydraulic lines and electrical connectors. Top up the hydraulic fluid (UTTO) and bleed the system if necessary.

6. 6

   Clear the Code

   Use a Massey Ferguson compatible diagnostic tool to clear the 0A.21.1A DTC and test the remote hydraulics for proper operation.