Massey Ferguson A.10.21 – Hydraulic Control Module or Vehicle Control Module: External Hydraulic Valve 1 Issue

Indicates a fault, often electrical or connection-related, with the first external hydraulic remote/spool valve on the tractor.

• 5710SL
• 5711SL
• 5712SL
• 5713SL
• T4
• 5608
• 5609
• 5610
• 5611
• 5612
• 5613
• 7714
• 7715
• 7715S
• 7716
• 7716S
• 7718
• 7718S
• 7719
• 7720
• 7720S
• 7722
• 7722S
• 7724
• 7724S
• 7726
• 7726S

1. 1

   Inspect the electrical connector at External Hydraulic Valve 1 for loose pins, dirt, or corrosion

2. 2

   Trace the wiring harness from the spool valve back to the control module to check for chafing, breaks, or short circuits

3. 3

   Use a compatible Massey Ferguson diagnostic tool to retrieve the code and monitor the live voltage/signal going to the valve solenoid when actuated

1. 1

   Isolate the Valve

   Locate External Hydraulic Valve 1 (usually the primary remote spool valve at the rear of the tractor).

2. 2

   Electrical Repair

   If the diagnostic checks reveal a wiring issue, clean the connector contacts with electrical contact cleaner or repair the damaged section of the wiring harness.

3. 3

   Component Replacement

   If the wiring is intact but the valve fails to respond to the control module's signal, the spool valve solenoid or the valve assembly itself must be replaced.

4. 4

   Clear Codes

   After replacing the valve or repairing the connection, use the diagnostic interface device to clear the 0A.10.21 code from the system.

5. 5

   Test

   Actuate the hydraulic remote to ensure proper fluid flow and verify that the code does not return.