Likely the sensor located on the HST pedal (or wiring circuit for this sensor)
The cruise control lever and HST pedal sensor are the same part number, so it is possible to swap to see if error code moves with sensor or stays with circuit.
Sensor is approximately $125
The sensor can be bench tested by monitoring resistance and rotating sensor slowly. There are two circuits within the sensor. One increases with rotation and the other decreases with rotation. Need to check both.
If a new sensor is needed it must be calibrated to the tractor. This can be done by accessing the Intellipanel and following the process outline in the WSM. It's a simple process, but a few steps must be followed.
Error codes can also be pulled or reset using the intellipanel. (See WSM)
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