Kubota E-R20 – Transmission Controller (TCU) / Instrumentation Controller: Trouble with the output voltage of the clutch pedal sensor

The clutch pedal sensor is a potentiometer (angular sensor) that measures the physical position of the clutch pedal to control the transmission's inching and shifting functions. When this code is triggered, the operator will hear 3 consecutive warning tones and see a flashing display on the dash.

• M95GX
• M100GX
• M105GX
• M110GX
• M115GX
• M125GX
• M126GX
• M128GX
• M135GX
• M6-101
• M6-111
• M6-121
• M6-131
• M6-141

1. 1

   Inspect the wiring harness and the electrical connector at the clutch pedal sensor for loose pins, corrosion, or wire chafing that could cause a voltage drop or open circuit.

2. 2

   Monitor the function of the pedal position potentiometer using the Kubota service tool or the TRANS VIEW screen on the instrumentation controller.

3. 3

   Perform a sweep test by watching the display while slowly cycling the inching (clutch) pedal. The position display should read 100% when fully released (up) and 0% when fully depressed. Erratic jumps indicate a failed potentiometer dead spot.

4. 4

   Verify that the sensor is receiving the correct reference voltage from the controller and that the signal voltage scales smoothly as the pedal is depressed.

1. 1

   Power Down

   Turn off the tractor and disconnect the negative battery cable to prevent electrical shorts.

2. 2

   Locate the Sensor

   Locate the clutch pedal angular sensor mounted on the clutch pedal pivot assembly under the dash/cab console.

3. 3

   Remove the Faulty Sensor

   Disconnect the electrical harness connector from the sensor. Remove the mounting screws securing the sensor to the pedal bracket and slide the sensor off the shaft.

4. 4

   Install the New Sensor

   Slide the new OEM clutch sensor onto the pedal shaft, ensuring the internal tangs align correctly with the pedal mechanism. Secure it with the mounting screws.

5. 5

   Reconnect

   Plug the electrical harness back into the sensor and reconnect the battery.

6. 6

   Calibration

   You must perform a clutch pedal calibration after replacing the sensor. Access the calibration menu via the service tool or instrumentation controller to teach the TCU the new 0% (fully depressed) and 100% (fully released) voltage values.