Case IH 2163 (519176.04) - DEC – Transmission Control Module (TCM): Synchro Low-mid Range Position Sensor - open circuit or short circuit to GND

The control module is receiving 'no signal' or an invalid low voltage signal from the synchro position sensor. This is typically caused by an open circuit (broken wire/connection) or a short circuit to ground, which pulls the signal voltage below the acceptable threshold.

• MAXXUM T4E
• Case IH MXM Series
• MXM120
• MXM130
• MXM140
• MXM155
• MXM175
• MXM190
• Case IH JX / JXC Series
• JX1100U
• JX1060C
• JX1070C
• Case IH Puma Series

1. 1

   Verify fork movement by pulling the transmission top plate, running the tractor, and ensuring the synchro forks are physically moving

2. 2

   Temporarily swap the synchro solenoids (e.g., swap the 1-4 synchro solenoid with the 5-8 synchro solenoid) to rule out a faulty solenoid

3. 3

   Test the signal voltage of the suspect low-mid range position sensor and compare it to a known good sensor on the transmission (such as the forward/reverse synchro sensor)

4. 4

   Swap the suspect position sensor with another synchro position sensor on the tractor. If the fault moves to the new location, the sensor is defective. If the fault stays in the low-mid range, the issue is in the wiring harness (open/short to ground)

1. 1

   Access transmission top plate

   Gain access to the transmission top plate where the synchro sensors and solenoids are located.

2. 2

   Remove retaining hardware

   Remove the M6 x 1 lock nut, M6 washer, and M7 circlip securing the faulty rotary position sensor.

3. 3

   Replace sensor

   Remove the defective sensor and install the replacement potentiometer.

4. 4

   Reassemble hardware

   Reassemble the retaining hardware (circlip, washer, and lock nut).

5. 5

   Perform transmission calibration

   You must perform a transmission calibration after installing the new sensor to clear the error and sync the TCM.