Causes and Fixes P0120 Code: Throttle/Pedal Position Sensor/Switch "A" Circuit Malfunction

How to fix P0120 Code: Throttle/Pedal Position Sensor/Switch "A" Circuit Malfunction A P0120 code is set when the computer (ECM/PCM) detects that the voltage from the throttle/pedal position sensor/switch is not within range. The "A" in this code refers to a specific sensor or circuit that can be different depending on the vehicle. The sensor on the throttle body is called the Throttle Position Sensor (TPS). The sensor on the gas pedal is called the Accelerator Pedal Position (APP). Some vehicles have a Throttle Body Relearn procedure if the sensors are replaced. Check the Throttle/Pedal Position Sensor voltage with the key on but the engine off. There needs to be a steady reference voltage (usually 5-volts) and a good ground. Possible Causes of a P0120 Code Dirty or Faulty Throttle Body Bad Throttle Position (TP) Sensor Bad Accelerator Pedal Position (APP) Sensor Wiring (Open - Short - Blown Fuse) Bad Computer (ECM/PCM/TAC) By using this information, the user assumes all risks of use.