Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car has a special sensor that checks how much pollution is coming out of the exhaust. This sensor has a heater to help it work better, but the heater isn't getting enough power.
The P23B2 code indicates that the control circuit for the NOx sensor heater in Bank 1, Sensor 3, is experiencing a low voltage condition.
The NOx sensor is responsible for measuring the levels of nitrogen oxides in the exhaust gases. This sensor has an integrated heater that ensures accurate readings by maintaining the sensor at an optimal temperature. The P23B2 code is triggered when the Engine Control Module (ECM) detects that the voltage in the heater control circuit is below the expected range, indicating a potential issue with the heater's power supply or the circuit itself.
• Check Engine Light illuminated
• Poor fuel efficiency
• Increased emissions
• Possible engine performance issues
• Faulty NOx sensor
• Damaged wiring or connectors in the sensor circuit
• Blown fuse for the sensor heater circuit
• Faulty ECM
NOx: Nitrogen Oxides, pollutants produced during combustion.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Check the fuse for the NOx sensor heater circuit.
• Test the NOx sensor heater resistance.
• Replace or repair damaged wiring or connectors.
• Replace the blown fuse.
• Replace the faulty NOx sensor.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Ford F-150
• Chevrolet Silverado
• Volkswagen Jetta
• Regular maintenance checks
• Keep electrical connections clean and secure
• Use high-quality fuel
Sensor Issue
• Do not ignore the Check Engine Light.
• Get the vehicle inspected by a professional mechanic.
Check with the vehicle manufacturer for specific warranty coverage on emissions-related components.
This code has become more common with the increased use of NOx sensors in modern vehicles to meet stricter emissions regulations.
Moderate – It should be addressed soon to prevent potential damage to the emissions system.
Driving with a faulty emissions system may be illegal in some regions and can lead to increased pollution.
• Engine at normal operating temperature
• Vehicle in a safe, stationary position
The NOx sensor is typically located in the exhaust system, downstream of the catalytic converter.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to increased emissions, reduced fuel efficiency, and potential damage to the emissions system.
Q: Can I drive my car with this code?
A: While the car may still be drivable, it's best to address the issue soon to avoid further problems.
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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.