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 detected a problem with the sensor that tells it how much you are pressing the gas pedal.
The P2120 code indicates an issue with the throttle/pedal position sensor/switch D circuit, which is responsible for monitoring the position of the throttle or gas pedal.
The throttle/pedal position sensor/switch D circuit is a part of the electronic throttle control system. It sends a signal to the engine control module (ECM) indicating the position of the throttle or gas pedal. If the ECM detects a voltage or resistance level outside of the expected range, it triggers the P2120 code.
• Check Engine Light illuminated
• Reduced engine power
• Unresponsive throttle
• Faulty throttle/pedal position sensor
• Damaged wiring or connectors
• ECM malfunction
Throttle: The mechanism that controls the amount of air entering the engine.
ECM: Engine Control Module, the computer that manages engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the throttle/pedal position sensor and its wiring for damage.
• Test the sensor's voltage and resistance levels.
• Replace the faulty throttle/pedal position sensor.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Screwdriver set
$100 - $300
Moderate
• Toyota Camry
• Ford F-150
• Chevrolet Silverado
• Regularly inspect and maintain the throttle system.
• Ensure connectors are secure and free from corrosion.
• Avoid harsh driving conditions that may damage sensors.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional.
• Avoid driving at high speeds until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on throttle system components.
The P2120 code has been a common issue in vehicles with electronic throttle control systems since their widespread adoption in the early 2000s.
Moderate – It is advisable to address this issue soon to avoid potential drivability problems.
Driving with a malfunctioning throttle position sensor can lead to reduced engine performance and may pose a safety risk.
• Engine must be running.
• Throttle system components should be at normal operating temperature.
The throttle/pedal position sensor is typically located near the throttle body or attached to the accelerator pedal assembly.
Q: Can I drive my car with a P2120 code?
A: It's possible, but not recommended as it may lead to reduced engine performance and could be unsafe.
Q: How can I reset the P2120 code?
A: You can use an OBD-II scanner to clear the code, but it's important to fix the underlying issue first.
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