Massey Ferguson 0A.4X.20 – Hydraulic Control Module or Auxiliary Valve Controller: External Hydraulic Valve 4 Issue

This indicates a malfunction, restriction, or electrical connection problem associated with the 4th rear remote spool valve (external hydraulic valve). This can result in the remote hydraulics being slow, weak, or completely dead.

• 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

   Inspect the hydraulic oil for contamination (dirt or debris) and check the hydraulic/transmission filters for blockages

2. 2

   Inspect the wiring harness and connector going to the #4 spool valve solenoid for corrosion, damage, or loose pins

3. 3

   Inspect the rear remote couplers for damage or blockages, and check hoses for leaks or wear

4. 4

   Test valve actuation to determine if the spool valve is physically stuck

1. 1

   Service the Fluid

   If the hydraulic fluid is dirty or burnt, drain the system and replace the hydraulic/transmission filters. Refill with clean, OEM-spec hydraulic fluid.

2. 2

   Repair Wiring

   If the diagnostic check revealed a wiring fault at the #4 valve, repair the damaged wires or replace the connector pigtail.

3. 3

   Clean/Free the Spool Valve

   If the valve is mechanically sticking, remove the #4 external hydraulic valve from the valve stack. Clean the spool and bore. Sometimes, manually moving the valve or cycling the controls can free a lightly stuck valve.

4. 4

   Replace the Valve

   If the solenoid is burnt out, the valve body is scored, or it fails to hold pressure after cleaning, the #4 external hydraulic valve must be replaced.

5. 5

   Clear Codes

   Use a compatible diagnostic tool to clear the 0A.4X.20 code and test the #4 remote with an implement to ensure proper pressure and flow.