P0123 Throttle Position Sensor/Switch A Circuit High Input

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P0123 Throttle Position Sensor/Switch A Circuit High Input

Technical Description

Throttle Position Sensor/Switch A Circuit High Input

What does that mean?

This diagnostic trouble code (DTC) is a generic powertrain code, which means that it applies to OBD-II equipped vehicles. Although generic, the specific repair steps may vary depending on make/model.

The TPS (Throttle Position Sensor) is a potentiometer that is mounted to the throttle body. It detects the throttle blade angle. As the throttle blade moves, the TPS sends a signal to the PCM (Powertrain Control Module), which is the main computer that runs the vehicle. Usually a three wire sensor: A 5 volt reference from the PCM to the TPS, a ground from the PCM to the TPS, and a signal return from the TPS to the PCM.

The TPS sends the throttle position information back to the PCM on this signal wire. When the throttle is closed the signal is near .45 volts. At WOT (Wide Open Throttle) the TPS signal voltage will approach a full 5 volts. When the PCM sees a voltage that is higher than the normal upper limit, P0123 will set.

Symptoms

  • Rough idle
  • High idle
  • Surging
  • other symptoms may also be present
  • Causes

    A code P0123 may mean that one or more of the following has happened:

  • TPS not mounted securely
  • TPS circuit short to ground or another wire
  • Faulty TPS
  • Damaged computer (PCM)
  • Possible Solutions

    A good starting point is always to check for technical service bulletins (TSB) for your particular vehicle. Your issue may be a known issue with a known fix put out by the manufacturer and can save you time and money during diagnosis.

    If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.

    If there are symptoms such as the engine is stumbling or hesitating, carefully inspect all wiring and connectors that lead to the TPS. More than likely the problem is with the TPS wiring.

    Check the voltage at the TPS (refer to a service manual for your vehicle for this specific information). If the voltage spikes or is too high (over 4.65 volts with key on, engine off), then that is indicative of a problem. Carefully trace each wire from the TPS wiring harness to check for breaks, rubbing against other components, etc.

    Other TPS sensor and circuit related DTCs: P0120, P0121, P0122, P0123, P0124

    Need help?

    Let us fix your problem. You are most welcome our diagnosis experts have in most cases the knowledge and skills to find the cause of the error code p0123 and to solve the problems.

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    "Delete Error Code Permanently, Disable DTC Error Code Function for p0123 in the ECU"

    In extreme cases, we even have the option to permanently remove the specific DTC p0123 and disable the function of the specific error code in the ECU. All other fault code functions will then continue to work to protect the engine. This is different from clearing an error code with a diagnostic device. We have the option to permanently remove the function of the specific error code, so that it never comes back. Also emergency running that occurs on the specific error code can be solved in most cases.

    Of course we prefer to first try to solve the cause of the error code, but sometimes the only solution is to permanently disable the DTC function of p0123.

    Make an appointment for permanent removal of p0123