Case IH 109 – TRANS: Low range clutch solenoid or its wiring failed open or shorted to ground.

The transmission controller has detected an electrical fault in the circuit responsible for actuating the low range clutch. The system is seeing either an open circuit (such as a broken wire, disconnected plug, or burnt-out solenoid coil) or a short to ground (bare wire touching the chassis or an internal solenoid short).

• MX Magnum
• STX Steiger
• Case IH MX Magnum Series
• Case IH TG Series
• Case IH Puma Series
• Case IH MXM Series
• Case IH Maxxum Series
• Case IH Steiger Series
• Case IH Farmall Series

1. 1

   Turn the ignition switch OFF, disconnect the low range clutch solenoid connector (often labeled X-641), and measure resistance between terminal 1 and 2 (should be 8 to 11 Ohms).

2. 2

   If resistance is infinite/open or near zero/shorted, the solenoid has failed. If within spec, proceed to check the wiring harness.

3. 3

   Disconnect the main transmission controller (CCU) connector (e.g., X-095) and turn the ignition switch ON.

4. 4

   Measure the voltage and continuity between the solenoid connector pins and ground to check for a short to positive voltage or a short to ground.

5. 5

   Inspect the wiring harness for chafing, pinched wires, or corrosion at the connectors.

1. 1

   Locate the Solenoid

   Locate the low range clutch solenoid. It is typically mounted on the transmission control valve block or the low-pressure oil distribution manifold on the side or top of the transmission housing.

2. 2

   Clean the Area

   Thoroughly clean the area around the transmission control valve to prevent dirt or debris from entering the hydraulic system.

3. 3

   Disconnect

   Unplug the electrical connector from the faulty low range clutch solenoid.

4. 4

   Remove

   Remove the retaining hardware (screws or retaining bracket) securing the solenoid to the valve body. Carefully pull the solenoid out.

5. 5

   Inspect

   Check the mounting port for any debris and ensure the old O-rings are not stuck inside the valve block.

6. 6

   Install

   Lubricate the O-rings on the new solenoid with clean transmission/hydraulic oil. Insert the new solenoid into the valve block and secure it with the retaining hardware.

7. 7

   Reconnect

   Plug the electrical connector back into the solenoid.

8. 8

   Calibrate

   Clear the fault codes using the tractor's diagnostic menu. Depending on the tractor model, you may need to perform a transmission clutch calibration procedure so the controller can learn the fill times for the new solenoid.