Case IH 2381 – Transmission Control Module (TCU): Open circuit or short circuit to + BAT of the 5th gear speed sensor

The engine speed and transmission shaft 5 speed are reading zero, while the voltage at the speed shaft sensor is greater than 4.5 V for 0.3 seconds.

• Steiger T4B
• Case IH STX Steiger & Quadtrac
• Case IH Puma
• Case IH Magnum

1. 1

   Clear the fault code using the tractor's diagnostic menu and restart the machine to see if the code returns immediately.

2. 2

   Inspect the wiring harness leading to the transmission speed sensors for any physical damage, breaks, or shorts to the battery positive.

3. 3

   Disconnect the 5th gear speed sensor. Ensure the connectors are fully seated, not damaged, and that the pins are tight and in the correct position.

4. 4

   With the sensor disconnected, check the circuit for continuity and verify if the voltage is inappropriately pegged above 4.5V due to a wiring short.

1. 1

   Locate the Sensor

   Identify the 5th gear/shaft speed sensor on the transmission housing. On Steiger models, there are typically three speed sensors located on the transmission (one on top towards the back, and two on the bottom left-hand side).

2. 2

   Disconnect and Remove

   Disconnect the electrical harness from the sensor. Remove the retaining bolt and carefully pull the sensor out of the transmission housing.

3. 3

   Transfer Spacers

   Retain the original spacer from the 5th gear sensor and install it on the new sensor. This is crucial to set the correct sensor depth into the transmission.

4. 4

   Install New Sensor

   Insert the new sensor (with the correct spacer) into the transmission housing and tighten the retaining hardware.

5. 5

   Reconnect and Clear

   Reconnect the electrical harness. Turn on the tractor, enter the diagnostic menu, clear fault code 2381, and test drive the machine to ensure normal shifting and that the code does not return.