Massey Ferguson 05.2.33 – HITCH: Issue With 4wd Solenoid Circuit (Hitch)

The onboard diagnostic (OBD) system has detected an electrical irregularity in the circuit responsible for controlling the 4-wheel drive (4WD) engagement solenoid. The fault is typically caused by an open circuit (e.g., a broken wire or disconnected plug), a short to ground, a short to power, or a failed solenoid coil.

• 4707
• 4708
• 4709
• 4710
• T4 (2015-2021)
• 5608-5613
• 5710SL-5713SL
• 7614-7626
• 7714-7726
• 8690

1. 1

   Visual Harness Inspection: Inspect the wiring harness leading to the 4WD solenoid (usually located on the right-hand rear pump cover or transmission housing) for rub points, melted insulation, or breaks.

2. 2

   Connector Integrity: Disconnect the plug at the 4WD solenoid. Check for water ingress, corrosion, or pushed-out pins.

3. 3

   Voltage Test: With the tractor key ON, toggle the 4WD switch in the cab (or press the brake pedals, which automatically engages 4WD on many models). Use a multimeter to verify if 12V is reaching the connector when the system commands 4WD to disengage.

4. 4

   Coil Resistance Test: Measure the resistance across the pins of the solenoid coil itself. An open circuit (infinite resistance/OL) or a dead short indicates a burned-out coil.

5. 5

   Ground Check: Verify that the ground wire in the harness has continuity to the chassis.

1. 1

   Preparation

   Park the tractor on a level surface, lower all implements, engage the parking brake, and turn off the engine. Chock the wheels.

2. 2

   Locate the Solenoid

   Locate the 4WD solenoid valve on the transmission housing/hydraulic pump cover (often grouped in a row of solenoids on the right-hand side behind the rear wheel).

3. 3

   Disconnect

   Unplug the electrical connector from the faulty 4WD solenoid.

4. 4

   Remove the Coil

   Remove the retaining nut at the top of the solenoid stem. Slide the faulty electromagnetic coil off the valve cartridge. (If the mechanical valve spool is sticking and also needs replacement, unscrew the entire valve cartridge from the manifold block. Have a drip pan ready for hydraulic fluid).

5. 5

   Install the New Part

   Slide the new solenoid coil over the valve stem and tighten the retaining nut (do not overtighten, as this can distort the sleeve). If replacing the whole cartridge, lubricate the new O-rings with clean hydraulic oil before threading it into the block.

6. 6

   Reassembly and Testing

   Reconnect the wiring harness. Clear the DTC codes using a diagnostic tool. Start the tractor, safely jack up one front wheel (if in a shop environment), and verify that the wheel can spin freely when 4WD is disengaged, and locks when 4WD is engaged.