Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer is getting a signal from the throttle or pedal position sensor that is too high. It's like if your video game controller was telling the game you were pressing the button all the way down, even if you weren't.
The P0123 code is triggered when the Engine Control Module (ECM) detects a voltage signal from the throttle position sensor that is higher than the expected range.
The Throttle Position Sensor (TPS) is used to monitor the position of the throttle in an internal combustion engine. The sensor is usually a potentiometer, and it provides a variable resistance depending on the position of the throttle valve. The ECM uses this information to adjust the air-fuel mixture and ignition timing. A P0123 code indicates that the TPS 'A' circuit is sending a voltage signal that is higher than the maximum threshold set by the manufacturer.
• Check Engine Light illuminated
• Poor engine performance
• Irregular or high idle speed
• Hesitation or stalling
• Faulty throttle position sensor
• Wiring issues such as shorts or opens in the TPS circuit
• Bad connections or corrosion at the sensor or ECM
• Faulty ECM
Throttle Position Sensor (TPS): A sensor that monitors the position of the throttle in an engine.
Engine Control Module (ECM): The computer that controls the engine's operation.
• Use an OBD-II scanner to confirm the code.
• Inspect the throttle position sensor and its wiring for damage.
• Check the voltage output from the TPS with a multimeter.
• Inspect connections and clean any corrosion.
• Replace the throttle position sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Clean connections and remove any corrosion.
• Replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Toyota Camry
• Regularly inspect and clean throttle body and sensors.
• Ensure all electrical connections are secure and corrosion-free.
• Perform routine maintenance checks on the vehicle's electrical system.
Sensor Issue
• Avoid driving the vehicle until the issue is resolved to prevent further damage.
• Consult a professional mechanic if unsure about performing repairs.
Check if the throttle position sensor is covered under the vehicle's powertrain warranty.
The P0123 code has been a common issue in vehicles with electronic throttle control systems since the late 1990s.
Moderate – While the vehicle may still be drivable, it can lead to poor performance and increased fuel consumption.
Ignoring this code can lead to safety issues such as unexpected acceleration or stalling. Always address OBD-II codes promptly.
• Engine running at operating temperature
• Throttle position sensor connected and functioning
The throttle position sensor is typically located on the throttle body, which is connected to the intake manifold.
Q: Can I drive with a P0123 code?
A: It's not recommended to drive with a P0123 code as it can lead to poor engine performance and potential safety issues.
Q: How do I reset the P0123 code?
A: After repairs, you can reset the code using an OBD-II scanner. However, ensure the issue is fixed to prevent the code from returning.
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Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
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Fitment Required · Vehicle-fitment part
Commonly relevant for misfire, ignition-efficiency, and some drivability-related repairs.
Misfire and ignition-related faults commonly involve spark plugs as part of the repair path.
Check the correct plug type, gap, and engine application for your vehicle.
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Fitment Required · Vehicle-fitment part
Relevant when the fault points toward ignition-coil performance or cylinder-specific ignition issues.
Some ignition faults involve coil performance or cylinder-specific coil problems.
Match the coil to your engine and confirm the failed component before ordering.
View options on AmazonThese parts may be related to this fault category, but a code by itself does not confirm exact fitment or guarantee that replacing a part will solve the problem.