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 the heater in the sensor that measures pollution gases from the engine. It's like a thermometer in your house not working right.
The NOx sensor heater is responsible for heating the NOx sensor to its optimal operating temperature. If the control circuit voltage is higher than expected, this code is triggered.
The P22A5 code indicates that the engine control module (ECM) has detected a high voltage condition in the heater control circuit of the NOx sensor located on Bank 1, Sensor 2. This sensor is part of the emissions control system and helps monitor the levels of nitrogen oxides (NOx) in the exhaust.
• Check Engine Light is on
• Increased emissions
• Possible decrease in fuel efficiency
• Faulty NOx sensor heater
• Wiring issues such as open or short circuits
• Faulty ECM or software issue
NOx: Nitrogen Oxides, a group of gases that are major pollutants from vehicle exhaust
ECM: Engine Control Module, the computer that controls engine functions
• Use an OBD-II scanner to verify the code
• Inspect the wiring and connectors for damage
• Test the NOx sensor heater circuit for proper voltage
• Replace the NOx sensor if faulty
• Repair or replace damaged wiring or connectors
• Reprogram or replace the ECM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Volkswagen Jetta
• Audi A3
• BMW 3 Series
• Regularly inspect and maintain the exhaust system
• Ensure software updates are performed
• Use quality fuel to prevent sensor contamination
Sensor Issue
• Do not ignore the Check Engine Light
• Have the vehicle inspected by a professional
• Avoid driving for extended periods if the light is flashing
Check with the vehicle manufacturer for emissions-related warranty coverage.
This code has become more common with the increased use of NOx sensors in modern vehicles to meet stricter emissions standards.
Moderate – It should be addressed soon to avoid potential emissions test failures and increased pollution.
Driving with a malfunctioning emissions system can lead to increased pollution and may not comply with local emissions laws.
• Engine at operating temperature
• Vehicle in closed-loop operation
The NOx sensor is typically located in the exhaust system, downstream from the catalytic converter.
Q: What does Bank 1 Sensor 2 mean?
A: Bank 1 refers to the side of the engine with cylinder 1, and Sensor 2 is the second sensor in the exhaust stream, usually after the catalytic converter.
Q: Can I drive with a P22A5 code?
A: While the vehicle may still be drivable, it is not recommended to ignore the issue as it can lead to increased emissions and potential engine performance 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.