Massey Ferguson A.42.19 – onboard diagnostic system / hydraulic control module: External Hydraulic Valve 4 Issue

Indicates a malfunction, restriction, or electrical connection problem on the 4th external hydraulic remote/spool valve circuit. This condition can result in the remote hydraulics becoming slow, weak, or completely dead, meaning the system cannot generate enough force to lift/hold a load, or the spool valve is unresponsive.

• 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

   Check hydraulic fluid (UTTO) for contamination or low levels, and inspect hydraulic and transmission filters for blockages.

2. 2

   Inspect the wiring harness and electrical connector going to External Valve 4 for connection problems to the solenoids.

3. 3

   Look for damaged couplers, worn hoses, or external leaks that could cause a pressure drop.

4. 4

   Check if the spool valve is physically sticking or if the relief valve is faulty.

1. 1

   Relieve Pressure

   Turn off the tractor and cycle the hydraulic controls to relieve all pressure from the hydraulic system before beginning work.

2. 2

   Drain/Catch Fluid

   Place a drain pan under the rear remote valve block to catch residual hydraulic fluid (UTTO).

3. 3

   Disconnect Electricals

   Unplug the electrical wiring harness connector from External Hydraulic Valve 4.

4. 4

   Remove Hoses and Couplers

   Disconnect the hydraulic lines and quick-connect couplers attached to the faulty spool valve.

5. 5

   Remove the Valve

   Unbolt the External Hydraulic Valve 4 assembly from the main hydraulic block/stack.

6. 6

   Rebuild or Replace

   Either install a completely new spool valve assembly or rebuild the existing valve using an OEM repair kit (replacing internal O-rings and seals).

7. 7

   Reinstall

   Bolt the new/rebuilt valve back into the stack. Reconnect all hydraulic lines and the electrical harness.

8. 8

   Service Fluids

   Replace the hydraulic filter and top off the system with clean UTTO (Universal Tractor Transmission Oil).

9. 9

   Test

   Start the tractor, allow the fluid to warm up, and test the remote valve for proper operation, ensuring there are no leaks and the fault code clears.