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 thinks the gas pedal is being pressed too much or is stuck. It's like when you press a button too hard and it doesn't work right.
The P2123 code is triggered when the Engine Control Module (ECM) detects a high voltage signal from the throttle/pedal position sensor/switch D circuit.
The throttle/pedal position sensor/switch D is part of the electronic throttle control system. It monitors the position of the accelerator pedal and sends this information to the ECM. A 'circuit high' condition indicates that the voltage signal from the sensor is higher than the expected range, which may suggest a malfunction in the sensor or wiring.
• Check Engine Light is on
• Unresponsive accelerator pedal
• Reduced engine performance
• Engine may enter 'limp' mode
• Faulty throttle/pedal position sensor
• Open or shorted wiring in the sensor circuit
• Poor electrical connection at the sensor
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics II
• Use an OBD-II scanner to confirm the code.
• Inspect the throttle/pedal position sensor and its wiring.
• Check for any loose or corroded connections.
• Test the sensor's voltage output with a multimeter.
• Replace the throttle/pedal position sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• Toyota Camry
• Ford F-150
• Chevrolet Silverado
• Regularly inspect and maintain the throttle system.
• Ensure electrical connections are clean and secure.
• Avoid exposure of sensors to moisture and dirt.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Avoid driving the vehicle aggressively until repaired.
Check with the vehicle manufacturer for warranty coverage on the throttle system components.
Throttle position sensor issues have been common in vehicles with electronic throttle control systems since their introduction.
Moderate – It should be addressed soon to prevent potential drivability issues.
Driving with a malfunctioning throttle position sensor can lead to unexpected acceleration or loss of power, which is a safety risk.
• Vehicle engine running
• Accelerator pedal operation
The throttle/pedal position sensor is usually located on the accelerator pedal assembly or near the throttle body.
Q: Can I drive my car with a P2123 code?
A: It's not recommended, as it can lead to reduced performance or safety issues.
Q: How do I clear the P2123 code?
A: After repairs, use an OBD-II scanner to clear the code and reset the ECM.
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