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 a sensor in your car's exhaust system, called the NOx sensor, is not working as fast as it should. It's like when you ask someone a question, and they take too long to answer.
The NOx sensor measures the amount of nitrogen oxides in the exhaust gases. A slow response means the sensor is not adjusting quickly enough to changes in exhaust gas composition.
The P23C0 code indicates that the NOx sensor on Bank 1, Sensor 3, is not responding quickly enough to changes in the exhaust gas composition. This slow response can affect the vehicle's ability to control emissions effectively.
• Check Engine Light is on
• Reduced fuel efficiency
• Possible increase in emissions
• Faulty NOx sensor
• Wiring issues or poor connections
• Exhaust leaks affecting sensor readings
NOx: Nitrogen Oxides, pollutants produced during combustion.
OBD-II: On-Board Diagnostics, a system to monitor vehicle performance.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connections to the NOx sensor.
• Check for exhaust leaks near the sensor.
• Replace the faulty NOx sensor.
• Repair or replace damaged wiring or connectors.
• Fix any exhaust leaks.
• OBD-II scanner
• Multimeter
• Wrench set
$200 - $500
Moderate
• Toyota Camry
• Ford F-150
• Chevrolet Silverado
• Regularly inspect and maintain exhaust system components.
• Ensure timely replacement of sensors as per manufacturer recommendations.
• Keep the vehicle's software updated.
Sensor Issue
• Do not ignore the Check Engine Light.
• Seek professional diagnosis if unsure.
• Regular maintenance can prevent such issues.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code has become more common with the increased use of NOx sensors in modern vehicles to meet emissions standards.
Moderate – Addressing this issue can prevent further emissions-related problems.
Driving with a malfunctioning NOx sensor may lead to increased emissions, which can be illegal in some regions.
• Engine running at operating temperature
• Vehicle driven under normal conditions
The NOx sensor is located in the exhaust system, typically after the catalytic converter on Bank 1.
Q: What does Bank 1 mean?
A: Bank 1 refers to the side of the engine with cylinder number 1.
Q: Can I drive with a P23C0 code?
A: It's possible to drive, but it's not recommended as it may lead to higher emissions and reduced fuel efficiency.
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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
Relevant when catalyst-efficiency or emissions faults persist after proper diagnosis.
Catalyst-efficiency faults sometimes point toward converter problems after proper testing.
Catalytic converters are highly vehicle-specific and should not be purchased by code alone.
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.