Case IH tD2 – PCU (Power Control Unit): Hand Throttle Position Sensor Potentiometer 1 Under Voltage

This code indicates that the signal voltage from the primary potentiometer circuit (Potentiometer 1) of the hand throttle position sensor has dropped below the acceptable minimum threshold. This typically points to a short to ground, an open circuit in the signal wire, a loss of the 5V reference supply, or an internal failure of the sensor itself.

• MXM
• MXM120
• MXM130
• MXM140
• MXM155
• MXM175
• MXM190
• MAXXUM 100
• MAXXUM 110
• MAXXUM 115
• MAXXUM 125
• MAXXUM 130
• MAXXUM 140
• PUMA 115 through 210

1. 1

   Inspect the wiring harness and connectors between the hand throttle position sensor (located in the right-hand cab console) and the PCU for chafing, corrosion, or backed-out pins.

2. 2

   Disconnect the sensor and turn the key to the ON position. Verify that the sensor is receiving a steady 5V reference and has a solid ground.

3. 3

   Check the Potentiometer 1 signal wire for continuity to the PCU. Test the wire for a short to ground or an open circuit.

4. 4

   Disconnect the potentiometer with the key switch in the ON position and then reconnect it to see if the code clears or changes, which can rule out a temporary poor connection.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent electrical spikes.

2. 2

   Access the Sensor

   Remove the necessary trim panels on the right-hand control console to access the hand throttle lever assembly.

3. 3

   Remove the Faulty Sensor

   Disconnect the electrical harness from the hand throttle position sensor. Remove the mounting screws securing the sensor to the throttle mechanism and remove the unit.

4. 4

   Install the New Sensor

   Mount the replacement sensor into position, secure the hardware, and plug in the electrical connector.

5. 5

   Reassemble and Power Up

   Reinstall the console trim panels and reconnect the battery.

6. 6

   Perform Calibration

   Enter the tractor's H-Menu/Calibration mode and perform the Transmission/EDC calibration to teach the PCU the new sensor's minimum and maximum voltage values.