Massey Ferguson A.21.18 – Onboard Diagnostic System: External Hydraulic Valve 2 Issue

A malfunction in the second remote hydraulic spool valve circuit, typically caused by a connection problem on the hydraulic valve or an issue with the spool position sensor value. This prevents the tractor from accurately reading the position of the spool or communicating with the valve's solenoid, leading to slow, weak, or dead remote hydraulics.

• 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 to 7726

1. 1

   Check the hydraulic fluid (UTTO) level and condition. Contaminated oil or a blocked hydraulic/transmission filter can restrict flow and cause valve faults.

2. 2

   Inspect the wiring harness leading to External Hydraulic Valve 2. Look for frayed wires, corrosion, or loose pins at the spool position sensor and solenoid connectors.

3. 3

   Test the spool position sensor using a compatible Massey Ferguson diagnostic tool to read live data from Valve 2. If the value is erratic or out of range, the sensor is likely faulty.

4. 4

   Inspect the remote couplers and hoses to ensure they are not damaged or blocked, which can cause pressure-related faults.

1. 1

   Depressurize the System

   Turn off the tractor and cycle the hydraulic remote levers/buttons to relieve all residual hydraulic pressure.

2. 2

   Access the Valve Block

   Locate the external hydraulic valve block (usually mounted at the rear above the rear axle or mid-mount depending on the loader configuration).

3. 3

   Disconnect Electronics

   Carefully unplug the electrical connectors for the solenoid and the spool position sensor on Valve 2.

4. 4

   Remove the Valve/Sensor

   If the diagnostic tool isolated the fault to the spool position sensor, unbolt and replace the sensor. If the valve itself is sticking or leaking internally, unbolt Valve 2 from the hydraulic stack.

5. 5

   Install New Parts

   Install the replacement sensor or rebuilt spool valve using new O-rings/seals. Torque the mounting bolts to OEM specifications.

6. 6

   Reassemble and Reconnect

   Reconnect the electrical harnesses.

7. 7

   Fluid Maintenance

   If the oil was contaminated, drain the hydraulic fluid, replace the hydraulic/transmission filter, and refill with fresh UTTO fluid (e.g., 10W40 hydraulic tractor fluid).

8. 8

   Clear Codes and Test

   Connect your diagnostic tool, clear the A.21.18 / 0A.21.18 DTC, and operate the remote valve with an implement to ensure normal pressure and flow.