Case IH 6023 - UCM – UCM / CCM: Four Wheel Drive (FWD) solenoid - open circuit

The control module is commanding the 4WD solenoid to activate or deactivate, but it cannot detect the electrical presence of the solenoid coil, usually due to a broken wire, a disconnected plug, or a burnt-out solenoid coil.

• MAXXUM T4E
• Case IH Puma Series (165, 180, 195, 210, 225 CVX)
• Case IH Magnum Series (MX210, MX230, MX255, MX285)
• Case IH Maxxum Series (115, 125, 135, MXM models)
• Case IH Steiger Series
• Case IH Farmall Series

1. 1

   Visually inspect the FWD solenoid electrical connector for secure connection, oil, dirt, or corrosion.

2. 2

   Test harness continuity from the FWD solenoid back to the UCM/CCM to check for chafed wires, pinch points, or breaks.

3. 3

   Perform a coil resistance test on the disconnected FWD solenoid (an 'OL' or infinite reading indicates a broken internal coil).

4. 4

   Perform a voltage test at the harness connector with the tractor running and 4WD engaged to rule out a UCM output failure.

1. 1

   Park the machine on a level surface, turn off the engine, relieve hydraulic pressure, and engage the parking brake.

   Ensure the machine is safe to work on.

2. 2

   Locate the FWD solenoid valve on the transmission control valve block.

   Refer to your specific model's service manual for the exact block location, usually near the differential lock and PTO solenoids.

3. 3

   Disconnect the electrical harness from the FWD solenoid.

   Prepare for harness inspection or solenoid removal.

4. 4

   If the harness is damaged: Splice and repair the broken wire using weather-sealed connectors, or replace the damaged connector pigtail.

   Address any wiring issues found during the diagnostic checks.

5. 5

   If the solenoid is faulty: Clean the area around the valve block.

   This prevents dirt from entering the hydraulic system.

6. 6

   Unscrew the retaining nut or mounting bolts holding the FWD solenoid cartridge in place and pull the solenoid out.

   Remove the faulty solenoid.

7. 7

   Lubricate the O-rings on the new FWD solenoid with clean hydraulic oil.

   Ensure proper sealing of the new component.

8. 8

   Install the new solenoid into the valve block and tighten to the OEM torque specification.

   Secure the new solenoid in place.

9. 9

   Reconnect the electrical harness.

   Restore electrical connection to the new solenoid.

10. 10

    Turn the ignition on, navigate the instrument cluster H-menu (or use a diagnostic tool) to clear the 6023 fault code, and test the 4WD engagement.

    Ensure the code does not return and the system operates correctly.