Massey Ferguson A.11.24 – Hydraulic Control Unit or Tractor Control Unit (TCU): External Hydraulic Valve 1 Issue

The control unit has detected a problem with the circuit, signal, or mechanical operation of the first auxiliary/external hydraulic spool valve. The system typically logs this when it sees a signal out of range, an open circuit, a short to ground, or when the valve spool fails to reach its commanded position due to mechanical jamming or low hydraulic pressure.

• 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

   Harness and Connector Inspection: Check the wiring harness leading to External Hydraulic Valve 1 for rub points, bare wires, or shorts to ground. Disconnect the solenoid connector and inspect for corrosion, moisture, or bent pins.

2. 2

   Solenoid Coil Resistance Test: Use a multimeter to measure the resistance of the valve's solenoid coil. Compare it to the OEM spec; an open circuit (infinite resistance) or a dead short indicates a failed coil.

3. 3

   Ground Integrity Check: Verify that the ground circuit for the valve block is clean and tight.

4. 4

   Mechanical Binding Check: Check if the valve spool is sticking or jamming due to internal debris or wear.

5. 5

   Hydraulic Fluid and Filter Check: Ensure the hydraulic fluid is at the correct level and the filters are not restricted, as low pressure can trigger valve actuation faults.

1. 1

   Power Down

   Turn off the tractor, remove the key, and relieve all hydraulic system pressure by moving the remote levers/joysticks through their full range of motion.

2. 2

   Clean the Area

   Thoroughly clean the rear remote valve block area to prevent dirt from entering the hydraulic system during disassembly.

3. 3

   Address Electrical Faults

   If the connector is corroded, clean the terminals with contact cleaner and apply dielectric grease. If the wiring harness is damaged, splice and heat-shrink the broken wires or replace the pigtail connector. If the solenoid coil failed the resistance test, remove the retaining nut on the end of the spool, slide the old coil off, and install a new solenoid coil.

4. 4

   Address Mechanical Faults

   If the valve is sticking, carefully remove the External Valve 1 cartridge/spool assembly from the valve block. Inspect the spool and bore for scoring, metal shavings, or damaged O-rings. Clean the spool with solvent. If it is heavily scored, the valve assembly must be replaced. Install the new or cleaned valve assembly with new O-rings, torquing to OEM specifications.

5. 5

   Reassembly and Testing

   Reconnect the electrical harness. Start the tractor, allow hydraulic pressure to build, and test the operation of Remote 1.

6. 6

   Clear Codes

   Use a compatible Massey Ferguson diagnostic tool to clear the 0A.11.24 code from the system memory.