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 has detected a problem with one of the sensors that checks how much pollution is coming out of the car's exhaust. It's like a thermometer for pollution, and it's not working right.
The NOx sensor measures nitrogen oxide levels in the exhaust to ensure the vehicle is not emitting too much pollution. This code indicates that the sensor is reading lower than expected.
P23AE indicates a low voltage condition in the NOx sensor circuit for Bank 1 Sensor 3. This sensor is responsible for monitoring the nitrogen oxide levels in the exhaust gases to help manage the vehicle's emissions. A low circuit condition may mean the sensor is not functioning correctly or there is an issue with the wiring or connections.
• Check Engine Light is on
• Poor fuel economy
• Increased emissions
• Faulty NOx sensor
• Wiring issues such as shorts or open circuits
• Poor electrical connections
NOx: Nitrogen Oxides, harmful pollutants produced by vehicles
OBD-II: On-Board Diagnostics, a standardized system for self-diagnosing vehicle issues
• Use an OBD-II scanner to confirm the code.
• Inspect the NOx sensor and its wiring for damage.
• Test the sensor's voltage and resistance.
• Replace the faulty NOx sensor.
• Repair or replace damaged wiring.
• Ensure all electrical connections are secure.
• OBD-II scanner
• Multimeter
• Socket set
$200 - $500
Moderate
• Toyota Camry
• Ford F-150
• Chevrolet Silverado
• Regular maintenance checks
• Use high-quality fuel
• Ensure timely replacement of sensors
Sensor Issue
• Avoid driving long distances until the issue is fixed.
• Consult a professional mechanic for accurate diagnosis.
Check if the vehicle's emissions warranty covers sensor replacement.
NOx sensor issues have become more common as emission standards have tightened, requiring more sensors in vehicles.
Moderate – It's important to address this issue to avoid increased emissions and potential damage to the catalytic converter.
Driving with a malfunctioning NOx sensor can lead to higher emissions, which may not comply with local environmental laws.
• Engine at operating temperature
• Vehicle in a well-ventilated area
The NOx sensor is typically located in the exhaust system, near the catalytic converter.
Q: Can I drive with a P23AE code?
A: It's possible to drive short distances, but it's best to fix the issue soon to avoid increased emissions and potential damage.
Q: How often should NOx sensors be replaced?
A: NOx sensors typically last around 100,000 miles, but this can vary based on driving conditions and maintenance.
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A wired color-screen reader with readiness hotkeys, live data, code definitions, and data logging.
Good for emissions-related codes because it exposes readiness monitors and live powertrain data.
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Specialty · Smoke machine
Helpful for finding EVAP and vacuum leaks that are hard to see with visual inspection alone.
Helpful for tracking down EVAP and vacuum leaks that can trigger emissions faults.
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Specialty · O2 sensor socket
Helpful when the code points toward exhaust or oxygen-sensor work and space is tight.
Useful when the diagnosis points toward oxygen-sensor removal or replacement.
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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.