Case IH F22 – Transmission Control Unit (TCU): Range Shift Synchronizer Did Not Disengage

This fault indicates a mechanical or electrical failure preventing the transmission's range shift synchronizer from properly disengaging when commanded. This is commonly caused by a failure in the high range clutch solenoid, a wiring harness issue (open circuit or short to ground/power), or a stuck synchronizer mechanism.

• MXM
• Puma 115
• Puma 125
• Puma 140
• Puma 155
• Puma 165
• Puma 180
• Puma 195
• Puma 210
• Puma 225
• Maxxum 110
• Maxxum 115
• Maxxum 120
• Maxxum 125
• Maxxum 130
• Maxxum 140
• Maxxum 155
• Maxxum 175
• Maxxum 190
• MXM 110
• MXM 115
• MXM 120
• MXM 125
• MXM 130
• MXM 140
• MXM 155
• MXM 175
• MXM 190
• Magnum 225

1. 1

   Locate the high range clutch solenoid on the transmission valve block and disconnect its electrical connector.

2. 2

   Perform a resistance test using a multimeter between solenoid terminal 1 and terminal 2. The resistance must be between 8 and 11 Ohms.

3. 3

   If the resistance is outside of the 8-11 Ohms range, the solenoid has failed internally and must be replaced.

4. 4

   If the solenoid tests within specifications, perform a wiring test to check for harness issues. Disconnect the UCM (Transmission Controller) connector, turn the ignition switch ON, and check for a short to positive voltage or a short to ground on the wires leading to the solenoid.

1. 1

   Access the Valve Block

   Locate the transmission control valve block (often located on the transmission side cover or top cover, depending on the specific tractor model).

2. 2

   Remove the Faulty Solenoid

   Disconnect the electrical harness from the high range clutch solenoid. Remove the retaining nut/hardware holding the solenoid coil and valve cartridge in place.

3. 3

   Install the New Solenoid

   Lubricate the O-rings on the new solenoid valve with clean transmission fluid. Insert the cartridge into the valve block and tighten the retaining hardware to factory specifications.

4. 4

   Reconnect Wiring

   Plug the electrical connector back into the solenoid.

5. 5

   Clear Codes

   Use the tractor's digital instrument cluster (EIC) or a diagnostic service tool to clear the F22 fault code.

6. 6

   Recalibrate

   After replacing transmission solenoids, it is highly recommended to perform a transmission clutch and synchronizer calibration procedure to ensure smooth shifting.