Throttle position
Throttle-position codes mean the pedal or throttle signal does not match the range the ECU expects.
P0122 is a low input and P0121 is a range or performance fault. The engine may hesitate, idle high, or enter a reduced-power mode.
Wiring and the throttle body belong in the same test as the sensor. The DTC page orders those checks.
A trouble code marks a condition to test. It does not by itself prove which part to replace.