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 having trouble reading the position of the gas pedal. It's like when a video game controller doesn't work right and your character doesn't move as expected.
The P1121 code is triggered when the Engine Control Module (ECM) detects a problem with the signal from the Pedal Position Sensor 1. This sensor helps the car understand how much the driver is pressing the gas pedal.
The Pedal Position Sensor 1 is responsible for providing the ECM with a voltage signal that corresponds to the position of the accelerator pedal. If the signal is outside the expected range or inconsistent, the ECM will set the P1121 code.
• Check Engine Light is on
• Poor acceleration
• Unresponsive throttle
• Faulty Pedal Position Sensor
• Wiring issues or poor connections
• Faulty ECM
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, Second Generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the Pedal Position Sensor.
• Test the Pedal Position Sensor for proper operation.
• Replace the Pedal Position Sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Reprogram or replace the ECM if necessary.
• OBD-II Scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Toyota Prius
• Ford Focus
• Nissan Altima
• Regularly inspect and maintain sensor connections.
• Ensure the pedal assembly is clean and free of debris.
• Perform routine diagnostic checks.
Sensor Issue
• Avoid driving if the car is not responding to the accelerator.
• Get the car checked by a professional mechanic as soon as possible.
Check if the vehicle's powertrain warranty covers sensor issues.
This code has been commonly reported in vehicles with electronic throttle control systems.
Moderate – Should be addressed soon to avoid potential drivability issues.
Driving with a malfunctioning accelerator pedal sensor can be dangerous. Address the issue promptly.
• Engine running
• Accelerator pedal pressed
The Pedal Position Sensor is located on the accelerator pedal assembly.
Q: Can I drive with a P1121 code?
A: It's not recommended as it can lead to unpredictable vehicle behavior.
Q: How do I reset the P1121 code?
A: After repairs, use an OBD-II scanner to clear the code from the ECM.
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