P0123 Fault Code

Throttle/Pedal Position Sensor/Switch A Circuit High Input

• What does that mean?
• Symptoms
• Causes
• Solutions

The P0123 fault code indicates a high input signal from the Throttle/Pedal Position Sensor/Switch A circuit. This sensor is critical for relaying the position of the throttle to the engine control unit (ECU), which in turn affects engine performance and emissions control. When the sensor sends a voltage that is too high, the ECU registers this fault code.

What are the symptoms of the P0123 code?

Symptoms of a P0123 code may entail:

• Check Engine Light (CEL) illuminated
• Poor engine performance or reduced power
• Erratic or unresponsive acceleration
• Engine stalling or hesitation while attempting to accelerate
• Potential increased fuel consumption.

What causes the P0123 code?

Possible causes of the P0123 code include:

• Faulty throttle position sensor
• Short circuit in the wiring or connectors
• Poor electrical connections or corrosion
• Issues with the accelerator pedal position sensor
• Faulty ECU or software issue
• Stuck or malfunctioning throttle body.

How to fix P0123?

To resolve the P0123 code, consider the following steps:

1. Inspect the throttle position sensor and related wiring for damage or shorts.
2. Check electrical connections for corrosion or loose fittings.
3. Test the throttle position sensor voltage and replace it if it’s faulty.
4. Ensure that the throttle body is clean and functioning properly.
5. If all else fails, consider reprogramming or replacing the ECU as a last resort.