Case IH FA2 – Transmission Control Unit (TCU) / Transmission Controller: Medium Range Clutch Solenoid Open Circuit Or Short To Ground

The transmission controller has detected an electrical fault—either a broken wire (open circuit), a short to the chassis ground, or a failed internal coil within the medium range clutch solenoid itself.

• MXM
• MXM Series
• MXM120
• MXM130
• MXM140
• MXM155
• MXM175
• MXM190
• MXU Series
• Maxxum Series
• Puma Series
• TM Series
• TM120 to TM190
• T6000
• T7 Series

1. 1

   Test the Solenoid Coil: Turn the ignition switch OFF, disconnect the electrical connector at the medium range clutch solenoid, and measure resistance between terminal 1 and terminal 2 (should read between 8 and 11 Ohms).

2. 2

   Check for Open Circuits: If the solenoid tests okay, check the wiring harness between the transmission controller and the solenoid connector for continuity on both the power and ground circuits.

3. 3

   Check for Shorts: Test the harness for a short to ground or a short to positive voltage. Repair any rubbed, pinched, or broken wires in the harness.

1. 1

   Preparation

   Park the tractor on level ground, lower all implements, turn off the engine, and block the wheels.

2. 2

   Removal

   Locate the transmission control valve block on the side of the transmission housing. Identify the medium range clutch solenoid. Disconnect the electrical connector.

3. 3

   Extraction

   Remove the retaining hardware (screws/plugs) holding the solenoid in place and pull the faulty solenoid valve from the manifold.

4. 4

   Installation

   Lubricate the O-rings on the new solenoid valve with clean transmission fluid. Insert the new solenoid into the valve block and torque the retaining hardware to spec. Reconnect the electrical connector.

5. 5

   Transmission Calibration

   The transmission controller must be recalibrated whenever a PWM solenoid valve is replaced. Enter calibration mode (typically by holding the High and Low range buttons while starting the engine until 'CAL' appears on the display). Set the engine speed to 1200 RPM. Follow the on-screen prompts to cycle through the clutch calibrations until the display reads 'END'.