The fault code P0122 OBD2 indicates that in the PCM (Powertrain Control Module) the TPS Sensor (Throttle Position Sensor) has detected that the voltage is below the limit already established. The lower limit varies according to the model since in some this limit goes from 0.17 to 0.20 volts. If the signal value is lower than 0.17 volts, diagnostic code P0122 is set.