Case IH tC5 – Transmission Controller / Power Control Unit (PCU): Engine Torque/RPM Sensor Short To Ground

The Engine Torque/RPM sensor measures engine speed and torque by monitoring the deflection of the flywheel damper spring. A short to ground indicates that the voltage signal from the sensor to the controller is being pulled to zero, usually due to internal sensor failure, a pinched wire, or chafed insulation touching the machine's chassis.

• MXM
• MXM120
• MXM130
• MXM135
• MXM140
• MXM155
• MXM175
• MXM190
• TM120
• TM130
• TM140
• TM155
• TM175
• TM190

1. 1

   Trace the wiring harness from the Engine Torque/RPM sensor (at the flywheel/bellhousing) to the transmission controller for pinched wires, melted insulation, or rubbing against the chassis

2. 2

   Disconnect the sensor and inspect the connector pins for corrosion, moisture, or damage bridging the signal wire to ground

3. 3

   With the sensor unplugged, use a multimeter to check for continuity between the signal wire on the harness side and the chassis ground to determine if the short is in the harness or the sensor itself

1. 1

   Power Down

   Turn off the machine, remove the key, and disconnect the negative battery cable to prevent electrical spikes.

2. 2

   Locate the Sensor

   Locate the Engine Torque/RPM sensor, which reads the flywheel damper spring deflection (typically mounted on the bellhousing/flywheel housing).

3. 3

   Remove the Sensor

   Disconnect the 3-pin electrical connector. Remove the retaining bolt and carefully pull the sensor out of the housing.

4. 4

   Repair Wiring

   If your diagnostic checks revealed a short in the wiring harness, splice and repair the damaged section using heat-shrink tubing, then re-loom the harness.

5. 5

   Install the New Sensor

   Insert the replacement sensor into the housing and tighten the retaining bolt.

6. 6

   Reconnect

   Plug the electrical connector back in and reconnect the battery.

7. 7

   Calibration

   Clear the stored fault codes and perform a Transmission/EDC calibration.