Massey Ferguson 0A.70.21 – onboard diagnostic system: External Hydraulic Valve 7 Issue

Indicates a malfunction, flow issue, or electrical connection problem with the 7th external hydraulic spool valve (remote valve) on the tractor's hydraulic valve block.

• 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

   Check the Datatronic 5 Terminal: Navigate to the hydraulics page to verify the flow settings and status of 'Valve 7'. Ensure the valve hasn't been electronically locked out or misconfigured.

2. 2

   Inspect Electrical Connections: Inspect the 4-pin electrical connector on the Valve 7 slice for corrosion, damaged wires, or loose seating.

3. 3

   Check Hydraulic Fluid: Verify the UTTO (Universal Tractor Transmission Oil) fluid level and condition. Contaminated fluid can cause spool valves to stick.

4. 4

   Inspect Filters: Ensure the hydraulic filters have been changed within their 300–500 hour service interval.

5. 5

   Visual Inspection: Check the external hydraulic valve block at the rear of the tractor for physical damage, leaking O-rings, or damaged quick couplers.

1. 1

   Preparation

   Park the tractor on a level surface, lower all implements to the ground, and turn off the engine. Relieve all hydraulic pressure in the system by cycling the hydraulic controls.

2. 2

   Disconnect Electricals

   Locate the external hydraulic valve block at the rear of the tractor. Identify Valve 7 and disconnect its 4-pin electrical connector.

3. 3

   Remove Hoses/Couplers

   Disconnect the hydraulic hoses and quick couplers attached to the faulty valve slice. Have a bucket ready to catch residual UTTO fluid.

4. 4

   Unbolt the Valve Slice

   Remove the retaining bolts securing the Valve 7 slice to the main hydraulic valve block assembly. Carefully separate the valve slice, ensuring you do not lose the internal standpipes or O-rings.

5. 5

   Install the New Valve

   Fit the new electric spool slice into the valve block, ensuring all O-rings and seals are correctly seated. Torque the retaining bolts to OEM specifications.

6. 6

   Reassembly

   Reconnect the hydraulic hoses, quick couplers, and the 4-pin electrical connector.

7. 7

   Programming

   Note that replacement electric spool slices often need to be programmed/calibrated to the tractor's ECU using a dealer diagnostic tool before they will function correctly.

8. 8

   Testing

   Top off the UTTO hydraulic fluid. Start the tractor, allow the fluid to warm up, and test the operation of Valve 7 via the cab controls. Check for leaks and clear the 0A.70.21 DTC.