Throttle Position Sensor (TPS) calculates throttle opening, as the throttle opens, the reading expressed in voltage, increases.
The vehicle’s main computer delivers a 5 volt reference signal to the TPS Sensor, plus a ground. If the vehicle is idling, this voltage should be 0.5. But if the vehicle is at full throttle there should be 4.5 volts.
If the PCM finds that the throttle angle is higher or lower than it should be for one Revolution Per Minute, the fault code P0226 OBDII will be stored. The letter C, refers to a particular part of the circuit.