P0123 Code - Throttle Position Sensor/Switch A Circuit High Input

Technical Description

Throttle Position Sensor/Switch A Circuit High Input

What does that mean?

A P0123 code means that the the car's computer has detected that the TPS (throttle position sensor) is reporting too high a voltage.

Symptoms

Symptoms may include:

• 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

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 Reading

SRT Forums

Need more help?

If you still need help regarding the P0123 trouble code, please post your concern in the forums.

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