Trouble Codes

P0120 Throttle (pedal position sensor) switch A – problem

DTC Description P0120 General

The throttle position sensor (TPS) is located on the throttle body. It is a type of variable resistor that changes its resistance value depending on the location of the damper. When the throttle is open, the voltage reading increases. This information is used by the ECM to determine output parameters such as fuel injection and idle air control.

Causes of general failure code P0120

  • Throttle position sensor defective
  • The throttle wiring harness assembly is open or shorted
  • Throttle position sensor circuit poor electrical connection
  • Engine Control Module (ECM

When will the code be detected?

The fault is detected when too low or high voltage from the sensor is sent to the ECM.
Symptoms of a general failure code P0120

  • The check engine light is on
  • No response to the accelerator pedal
  • Increased engine speed
  • See entries