Massey Ferguson 05.0.33 – HITCH: Issue With 4wd Solenoid Circuit (Hitch)

The control module has detected an electrical anomaly—such as an open circuit, short to ground, or short to power—in the wiring or the coil of the 4-Wheel Drive (4WD) engagement solenoid, causing the tractor to default to constant 4WD.

• 4707
• 4708
• 4709
• 4710
• T4 (2015-2021)
• 5608-5613
• 5710SL-5713SL
• 7614-7626
• 7714-7726
• 8600 Series

1. 1

   Check the Brake Light Switch: A faulty or misadjusted brake switch (located above the pedals) can cause intermittent 4WD circuit issues.

2. 2

   Solenoid Swap Test: Swap the electrical connectors or the coils between the 4WD and Diff-Lock solenoids to see if the fault code changes to a Diff-Lock circuit error (e.g., 05.0.53).

3. 3

   Direct Power Test ("Hotwire"): Apply 12V directly to the 4WD solenoid to see if it clicks and disengages the 4WD, which would point to a wiring break or bad switch.

4. 4

   Harness Inspection: Inspect the wiring harness leading to the transfer box/right-hand hydraulic cover plate for chafing, melted wires, or corroded connector pins.

1. 1

   Locate the Solenoid

   The 4WD solenoid is typically located on the right-hand hydraulic cover plate, inside the transfer box, or on the front PTO housing (depending on the exact model).

2. 2

   Prep the Area

   Clean the area around the solenoid to prevent dirt from entering the hydraulic system. Place a catch pan underneath, as a small amount of hydraulic oil may leak.

3. 3

   Remove the Coil

   Disconnect the electrical connector. Remove the retaining nut at the top of the solenoid stem and slide the electromagnetic coil off the valve cartridge.

4. 4

   Remove the Valve (If necessary)

   If the mechanical spool valve is stuck, use a wrench to unthread the valve cartridge from the housing.

5. 5

   Install New Parts

   Thread the new valve cartridge into the housing and tighten to OEM torque specs. Slide the new coil over the stem and secure it with the retaining nut.

6. 6

   Reconnect and Clear Codes

   Reconnect the wiring harness. Turn on the tractor and use the diagnostic interface to clear the DTC codes.

7. 7

   Test

   Test drive the tractor to ensure 4WD engages and disengages via the cab switch, and verify that 4WD engages automatically when both brake pedals are depressed.