Engine-CodesToyota – P0123 Toyota

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

Quick Answer

The P0123 diagnostic trouble code (DTC) for Toyota vehicles indicates a problem with the Throttle/Pedal Position Sensor/Switch 'A' Circuit having a high input. Common causes include Faulty Throttle Position Sensor: The sensor itself may be malfunctioning, sending incorrect voltage signals to the ECM, Damaged Wiring or Connectors: Corrosion, breaks, or poor connections in the wiring harness or sensor connectors can disrupt the signal transmission, ECM Malfunction: A problem with the engine control module could also be causing the high input signal. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means
P0123 Toyota indicates Throttle / Pedal Position Sensor / Switch 'A' Circuit High Input.
Common causes
Common causes include Faulty Throttle Position Sensor: The sensor itself may be malfunctioning, sending incorrect voltage signals to the ECM, Damaged Wiring or Connectors: Corrosion, breaks, or poor connections in the wiring harness or sensor connectors can disrupt the signal transmission, ECM Malfunction: A problem with the engine control module could also be causing the high input signal.
Severity
High - diagnose this code as soon as possible.
Can I drive?
Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Table of contents Created and updated by William Orellana on Sep 12, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P0123 Toyota Description

The P0123 diagnostic trouble code (DTC) for Toyota vehicles indicates a problem with the Throttle/Pedal Position Sensor/Switch 'A' Circuit having a high input. This sensor is responsible for monitoring the position of the throttle pedal and sending this information to the engine control module (ECM) to adjust fuel delivery and engine performance accordingly. When the sensor detects a high input signal, it means that the voltage being sent to the ECM is outside of the normal operating range, potentially leading to improper engine performance and drivability issues.

OBDII Code P0123 Toyota - Throttle / Pedal Position Sensor / Switch 'A' Circuit High Input
P0123 Toyota Code - Throttle / Pedal Position Sensor / Switch 'A' Circuit High Input

Common Causes of P0123 Toyota

  1. Faulty Throttle Position Sensor: The sensor itself may be malfunctioning, sending incorrect voltage signals to the ECM.
  2. Damaged Wiring or Connectors: Corrosion, breaks, or poor connections in the wiring harness or sensor connectors can disrupt the signal transmission.
  3. ECM Malfunction: A problem with the engine control module could also be causing the high input signal.
  4. Throttle Pedal Position Sensor/Switch 'A': Issues with the throttle pedal position sensor or switch itself could lead to this code.
  5. Environmental Factors: Exposure to extreme temperatures or moisture can also contribute to sensor malfunction.

Symptoms of P0123 Toyota

  1. Check Engine Light: The most common symptom associated with this code is the illumination of the check engine light on the vehicle's dashboard.
  2. Reduced Acceleration: Drivers may experience a lack of response or reduced acceleration when pressing on the throttle pedal.
  3. Inconsistent Engine Performance: The engine may exhibit erratic behavior, such as surging or hesitation during acceleration.
  4. Rough Idle: The vehicle may have difficulty maintaining a smooth and consistent idle speed.
  5. Stalling: In severe cases, the engine may stall unexpectedly while driving or idling.

How to Fix P0123 Toyota

  1. Diagnostic Scan: Use an OBD-II scanner to retrieve the trouble code and identify the specific issue causing the high input signal.
  2. Inspect Wiring and Connectors: Check the throttle position sensor wiring and connectors for any damage, corrosion, or loose connections.
  3. Test Throttle Position Sensor: Use a multimeter to test the sensor's voltage output and compare it to the manufacturer's specifications.
  4. Replace Faulty Components: If the throttle position sensor or wiring is found to be faulty, replace the sensor and repair any damaged wiring or connectors.
  5. Clear Codes and Test Drive: Clear the DTC from the ECM memory, and test drive the vehicle to ensure that the issue has been resolved.

Cost to Fix P0123 Toyota

The cost of repairing a P0123 Throttle/Pedal Position Sensor/Switch 'A' Circuit High Input code can vary depending on the specific cause of the issue and the labor rates in your area. Typically, the cost of a new throttle position sensor ranges from $50 to $200, while the labor cost for diagnosis and replacement can range from $100 to $300. Overall, the total repair cost could be between $150 and $500, including parts and labor. However, it is recommended to obtain quotes from local auto repair shops to get a more accurate estimate based on your vehicle make and model, as well as the severity of the issue. Keep in mind that labor rates can vary, with hourly rates typically ranging from $80 to $150.

Tech Notes for P0123 Toyota

Quite a frequent problem with Toyota models. Before replacing any parts, try cleaning the throttle body and resetting the code. If the code comes back, it will be necessary to replace the Throttle Body Assembly.











User Submitted Video

Need more information about the P0123 Toyota code?

Need more information on how to fix the P0123 Toyota code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0123 Toyota code diagnosed by a professional: Find a repair shop in your area

Information for Specific Toyota Models

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0123 Toyota Code

1. What does the OBDII code P0123 mean on a Toyota?

P0123 indicates that the Throttle/Pedal Position Sensor (TPS) 'A' circuit has a high input voltage, meaning the sensor is reporting a voltage above its expected range.

2. What are the symptoms of a P0123 code in a Toyota?

Common symptoms include poor engine performance, difficulty accelerating, high or erratic idle, stalling, and the check engine light being illuminated.

3. What causes the P0123 code to appear on a Toyota?

Possible causes include a faulty throttle position sensor, damaged wiring or connectors, a stuck throttle body, or a malfunctioning engine control module (ECM).

4. How do I diagnose a P0123 code on my Toyota?

Start by inspecting the TPS and its wiring for damage or corrosion, check the throttle body for proper operation, and use a multimeter to test the TPS voltage range.

5. Can I drive my Toyota with a P0123 code?

Driving with a P0123 code is not recommended, as it may cause poor performance, stalling, or unsafe driving conditions.

6. How do I fix the P0123 code on a Toyota?

Repairs may involve replacing the throttle position sensor, repairing or replacing damaged wiring or connectors, cleaning the throttle body, or, in rare cases, replacing the ECM.

7. How much does it cost to fix a P0123 code on a Toyota?

The cost depends on the specific repair needed. Replacing a TPS typically costs $100–$300 for parts and labor, but wiring repairs or ECM replacement may be more expensive.

8. Can a dirty throttle body cause the P0123 code?

Yes, a dirty or sticking throttle body can cause incorrect voltage readings from the TPS, potentially triggering the P0123 code.

9. How do I prevent the P0123 code from recurring?

Regular maintenance, including cleaning the throttle body, inspecting the TPS and wiring, and addressing check engine lights promptly, can help prevent recurrence.

10. Will clearing the P0123 code with a scanner fix the problem?

Clearing the code may turn off the check engine light temporarily, but the underlying issue must be repaired to prevent the code from returning.

Discuss the causes and fixes for P0123 Toyota OBDII Code

Code P0123 Toyota comments

No comments found for this page.