Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
The car's computer is saying that the oxygen sensor on one side of the engine isn't getting enough power to work properly.
The O2 sensor measures the amount of oxygen in the exhaust. This code indicates that the voltage from the sensor is lower than expected.
The P2249 code is triggered when the Powertrain Control Module (PCM) detects a low voltage condition in the reference circuit of the oxygen sensor located on Bank 2, Sensor 1. This sensor is responsible for monitoring the oxygen levels in the exhaust gases before the catalytic converter.
• Check Engine Light illuminated
• Poor fuel economy
• Rough engine idle
• Faulty oxygen sensor
• Wiring issues such as short circuits or open circuits
• Faulty PCM
PCM: Powertrain Control Module
O2 Sensor: Oxygen Sensor
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the oxygen sensor's voltage output.
• Repair or replace damaged wiring or connectors.
• Replace the faulty oxygen sensor.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Toyota Camry
• Honda Accord
• Ford F-150
• Regularly inspect and maintain the vehicle's exhaust system.
• Ensure all electrical connections are secure and free of corrosion.
• Use high-quality fuel to prevent sensor contamination.
Sensor Issue
• Avoid driving long distances until the issue is resolved.
• Have the vehicle inspected by a professional mechanic.
Oxygen sensors may be covered under the vehicle's emissions warranty.
This code has been reported in various models, often due to sensor wear or electrical issues.
Moderate – Should be addressed soon to avoid further engine performance issues.
Driving with a faulty oxygen sensor can lead to increased emissions and may not comply with local emissions regulations.
• Engine at operating temperature
• Vehicle in closed-loop operation
The oxygen sensor is located in the exhaust manifold on the side of the engine opposite the number one cylinder (Bank 2).
Q: Can I drive with a P2249 code?
A: It's not recommended to drive for long periods with this code, as it can lead to poor engine performance and increased emissions.
Q: How do I know if my oxygen sensor is bad?
A: Symptoms include a rough idle, poor fuel economy, and the Check Engine Light being on.
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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 the code or supporting diagnostics point toward upstream or downstream oxygen-sensor faults.
This code family often involves upstream or downstream oxygen-sensor diagnosis.
Verify exact sensor position and vehicle fitment before buying.
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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.