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 gas pedal sensor that is too high, like the pedal is pressed down too much when it's not.
The P1123 code indicates that the signal from the pedal position sensor 1 is higher than the expected range. This could mean a problem with the sensor or the wiring.
The pedal position sensor monitors the position of the accelerator pedal. When the sensor sends a voltage signal that is higher than the expected range, the Engine Control Module (ECM) detects this as a fault and triggers the P1123 code.
• Check Engine Light is on
• Poor acceleration
• Unresponsive throttle
• Faulty pedal position sensor
• Wiring issues or poor connections
• Defective 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 connectors for damage.
• Test the pedal position sensor with a multimeter.
• Replace the pedal position sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Nissan Altima
• Hyundai Sonata
• Kia Optima
• Regularly inspect wiring and connectors.
• Keep the throttle body clean.
• Ensure proper maintenance of the ECM.
Sensor Issue
• Avoid driving aggressively until the issue is resolved.
• Have the vehicle inspected by a professional mechanic.
Sensor-related issues may be covered under the vehicle's powertrain warranty.
This code has been more common in vehicles with electronic throttle control systems.
Moderate – It is recommended to address this issue soon to avoid potential drivability problems.
Ignoring this code could lead to unsafe driving conditions due to throttle response issues.
• Vehicle must be in a safe, stationary position.
• Ensure the engine is off before testing the sensor.
The pedal position sensor is located near the accelerator pedal assembly.
Q: Can I drive with a P1123 code?
A: It's not recommended, as it can affect throttle response and lead to unsafe driving conditions.
Q: How do I reset the P1123 code?
A: After repairs, use an OBD-II scanner to clear the code. If the issue is fixed, it should not return.
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