Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the power going to a special sensor in your car that checks the pollution levels. It's like the sensor isn't getting enough electricity to do its job.
The P220B code indicates an issue with the supply voltage circuit for the NOx sensor located in Bank 1, Sensor 2. This sensor is responsible for measuring nitrogen oxide levels in the exhaust.
The NOx sensor is crucial for monitoring and controlling emissions. The P220B code is triggered when the Engine Control Module (ECM) detects an abnormal voltage level in the supply circuit of the NOx sensor on Bank 1, Sensor 2. This can affect the sensor's ability to accurately measure NOx levels.
• Check Engine Light is on
• Possible decrease in fuel efficiency
• Increased emissions
• Faulty NOx sensor
• Wiring issues or poor connections
• Failed ECM or control module
NOx Sensor: A component that measures nitrogen oxides in the exhaust gases.
Bank 1: The side of the engine with cylinder 1, typically the side where the number 1 cylinder is located.
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connectors for damage
• Test the NOx sensor voltage supply
• Repair or replace damaged wiring
• Replace the NOx sensor if faulty
• Reprogram or replace the ECM if necessary
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $600
Moderate
• Volkswagen Jetta
• Audi A4
• BMW 3 Series
• Regular maintenance and inspections
• Ensure clean and secure electrical connections
• Timely replacement of faulty sensors
Sensor Issue
• Have the vehicle inspected by a professional mechanic
• Avoid ignoring the Check Engine Light
• Consider regular diagnostics to catch issues early
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 emission standards.
Moderate – Should be addressed soon to prevent increased emissions and potential engine performance issues.
Driving with a malfunctioning NOx sensor could lead to failing emissions tests and contribute to environmental pollution.
• Engine at operating temperature
• Vehicle running at various speeds
The NOx sensor for Bank 1, Sensor 2 is typically located downstream in the exhaust system, often after the catalytic converter.
Q: Can I drive with a P220B code?
A: It's possible to drive, but it's not recommended as it can lead to higher emissions and potential damage over time.
Q: How can I prevent a P220B code?
A: Regular maintenance and ensuring your vehicle's sensors and wiring are in good condition can help prevent this code.
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Universal · Digital multimeter
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Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
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Universal · Wire connectors and repair kit
Useful when diagnosis points toward damaged wiring, corroded terminals, or connector repairs.
Useful if diagnosis points toward damaged connectors, wiring, or terminal 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.