Case IH 107 – Transmission Controller (TRANS): C5-6 clutch solenoid or its wiring failed open or shorted to ground

The control module has detected an electrical fault in the circuit responsible for actuating the C5-6 transmission clutch pack. The system is seeing either infinite resistance (an open circuit, such as a broken wire or burnt-out solenoid coil) or zero resistance to ground (a short circuit, where a bare wire is touching the tractor's chassis or the coil has internally shorted).

• MX Magnum
• STX Steiger
• MX Magnum Series
• Magnum Series
• Steiger / Quadtrac Series
• TG Series

1. 1

   Inspect the wiring harness running from the Transmission Controller to the powershift valve block for chafed wires, melted insulation, or loose/corroded pins at the C5-6 solenoid connector.

2. 2

   Disconnect the C5-6 solenoid and measure the resistance across the solenoid's pins with a multimeter. A healthy coil reads 6.8 to 8.0 ohms. 'OL' indicates a burnt-out coil, and near 0 ohms indicates an internal short.

3. 3

   Check the harness side of the connector for continuity back to the Transmission Controller. Check both wires for continuity to the tractor chassis ground to rule out a shorted harness.

4. 4

   Swap the C5-6 clutch solenoid with an adjacent, identical clutch solenoid on the valve block (such as C3-4 or C1-2). Clear codes and cycle the key. If the fault code changes to match the new location, the solenoid is faulty. If Code 107 remains, the issue is in the wiring harness or the Transmission Controller.

1. 1

   Preparation

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

2. 2

   Locate the Valve Block

   Locate the transmission powershift valve block, typically mounted on the side or top of the transmission housing. Identify the C5-6 solenoid (refer to the specific model's service manual diagram for exact placement on the block).

3. 3

   Clean the Area

   Thoroughly clean the area around the solenoid with brake cleaner or compressed air to prevent dirt from entering the transmission's hydraulic system.

4. 4

   Removal

   Disconnect the electrical connector from the C5-6 solenoid. Remove the retaining nut or bolt securing the solenoid coil/cartridge. Carefully pull the solenoid cartridge straight out of the valve block. Have a catch pan ready, as a small amount of transmission fluid will leak out.

5. 5

   Inspection

   Inspect the valve bore inside the manifold for scoring, debris, or leftover O-ring material.

6. 6

   Installation

   Lubricate the O-rings on the new solenoid cartridge with clean Case IH Hy-Tran fluid. Carefully insert the new solenoid into the bore, ensuring it seats fully without pinching the O-rings.

7. 7

   Secure and Reconnect

   Install the retaining hardware and torque to OEM specifications. Reconnect the electrical harness.

8. 8

   Calibration

   Start the tractor, check for leaks, and clear the fault codes. You must perform a transmission clutch calibration procedure via the tractor's display/monitor so the Transmission Controller can learn the fill times and modulation characteristics of the new solenoid.