Case IH 6025 – Transmission Control Unit (TCU) or Chassis Control Module (CCM): FWD / MFD Clutch Solenoid Circuit Error

Indicates a circuit error (short to ground or +12V) on the FWD (Front Wheel Drive) / MFD (Mechanical Front Drive) clutch solenoid. The controller detects a short and disables the output to protect the module, preventing the solenoid from energizing and causing the tractor to default to being stuck in 4WD.

• MAXXUM T4E
• Case IH Puma series
• Case IH Magnum series
• Case IH Maxxum series
• Case IH Steiger series

1. 1

   Check the fuse panel for a blown FWD/MFD circuit fuse, which often pops if there is a dead short in the solenoid coil.

2. 2

   Inspect the wiring harness from the transmission valve block to the cab bulkhead for chafing, pinched wires, or melted insulation.

3. 3

   Test the solenoid coil resistance with a multimeter (healthy is 7-14 ohms; near 0 ohms indicates an internal short).

4. 4

   Check for ground shorts by disconnecting the solenoid and TCU, then probing the power supply wire for continuity to chassis ground.

1. 1

   Prepare machine

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and remove the key.

2. 2

   Locate solenoid

   Locate the FWD/MFD solenoid. It is typically mounted on the transmission valve block, located on the side or bottom of the transmission housing near the MFD drop box/transfer case.

3. 3

   Disconnect harness

   Disconnect the electrical harness connector from the solenoid.

4. 4

   Clean area

   Thoroughly clean the area around the valve block with brake cleaner to prevent dirt from entering the hydraulic system.

5. 5

   Remove retaining nut

   Remove the retaining nut at the end of the solenoid stem.

6. 6

   Remove old coil

   Slide the old solenoid coil off the valve cartridge. (Note: If the cartridge itself is leaking or sticking, you can unscrew the cartridge from the block. Have a catch pan ready for a small amount of hydraulic fluid loss).

7. 7

   Install new coil

   Slide the new solenoid coil onto the stem and tighten the retaining nut (do not overtighten, or you may crack the plastic coil housing).

8. 8

   Reconnect harness

   Reconnect the electrical harness.

9. 9

   Clear fault code

   Turn the key on and use the AFS Pro display (or diagnostic tool) to clear the stored 6025 fault code.

10. 10

    Test drive

    Test drive the tractor, toggling the 4WD switch to ensure the MFD engages and disengages properly.