Massey Ferguson 0A.33.1A – Tractor Control Unit (TCU) or Auxiliary Valve Controller: External Hydraulic Valve 3 Issue

The tractor's onboard diagnostic system has detected a malfunction, electrical fault, or communication error specifically isolated to the third rear auxiliary hydraulic remote valve (spool valve 3).

• 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 electrical connector and wiring harness leading to External Hydraulic Valve 3 for damage, corrosion, or loose pins.

2. 2

   Test the solenoid coil on Valve 3 for proper resistance and verify it is receiving voltage from the controller when activated.

3. 3

   Swap the electrical connection or the solenoid coil with an adjacent working valve (e.g., Valve 2 or 4). If the fault code changes to the new valve location, the solenoid is faulty. If the code remains 0A.33.1A, the issue is in the wiring harness or the ECU.

4. 4

   Check the hydraulic valve for physical binding, sticking, or leaks. Ensure hydraulic fluid levels are correct and free of contamination that could cause the spool to jam.

1. 1

   Park the tractor on a level surface, turn off the engine, and relieve all hydraulic system pressure by cycling the remote levers/buttons.

   Relieve all hydraulic system pressure by cycling the remote levers/buttons.

2. 2

   Disconnect the negative battery cable to prevent electrical shorts.

   Prevent electrical shorts.

3. 3

   Locate External Hydraulic Valve 3 at the rear remote valve stack.

   Locate External Hydraulic Valve 3.

4. 4

   Disconnect the electrical harness connector from the valve's solenoid.

   Disconnect the electrical harness connector.

5. 5

   If replacing the solenoid: Remove the retaining nut/screws, slide the old solenoid off the valve stem, and install the new solenoid.

   Remove the retaining nut/screws, slide the old solenoid off the valve stem, and install the new solenoid.

6. 6

   If replacing or rebuilding the spool valve: Unbolt the specific valve section from the hydraulic stack.

   Unbolt the specific valve section from the hydraulic stack.

7. 7

   Clean the mating surfaces thoroughly. If rebuilding, replace all internal O-rings and seals using an OEM repair kit.

   If rebuilding, replace all internal O-rings and seals using an OEM repair kit.

8. 8

   Install the new or repaired spool valve, torque the tie-bolts to the manufacturer's specification, and reconnect the electrical harness.

   Torque the tie-bolts to the manufacturer's specification, and reconnect the electrical harness.

9. 9

   Reconnect the battery, start the tractor, and check for hydraulic leaks.

   Check for hydraulic leaks.

10. 10

    Use a compatible diagnostic tool to clear the 0A.33.1A fault code and test the operation of Valve 3.

    Clear the 0A.33.1A fault code and test the operation of Valve 3.