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 oxygen sensor in the engine. The sensor is sending too much power, which is not normal.
The P2239 code indicates that the power supply to the oxygen sensor on Bank 1 Sensor 1 is higher than expected, suggesting a possible short or fault in the sensor circuit.
The oxygen sensor measures the amount of oxygen in the exhaust gases and sends this information to the engine control module (ECM). The ECM uses this data to adjust the air-fuel mixture for optimal combustion. The 'Positive Current Control Circuit High' indicates that the current supplied to the sensor is higher than the specified range, which can affect sensor operation and engine performance.
• Check Engine Light illuminated
• Poor fuel economy
• Rough engine idle
• Faulty oxygen sensor
• Wiring issues such as shorts or open circuits
• Faulty ECM
Oxygen Sensor: A device that measures the amount of oxygen in the exhaust gases.
ECM: Engine Control Module, the computer that controls engine functions.
• Use an OBD-II scanner to confirm the code.
• Inspect the oxygen sensor wiring for damage.
• Test the oxygen sensor for proper operation.
• Replace the faulty oxygen sensor.
• Repair or replace damaged wiring.
• Replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Wrench set
$150 - $400
Moderate
• Toyota Camry
• Honda Accord
• Ford F-150
• Regularly inspect and maintain oxygen sensors.
• Ensure wiring harnesses are secure and undamaged.
• Use high-quality fuel to prevent sensor contamination.
Sensor Issue
• Avoid driving the vehicle for extended periods with this code active.
• Have the vehicle inspected by a professional mechanic.
• Monitor fuel economy for any significant changes.
Oxygen sensors may be covered under the vehicle's emissions warranty, typically up to 8 years or 80,000 miles.
The P2239 code has been more common in vehicles with higher mileage or those that frequently experience harsh driving conditions.
Moderate – While the vehicle may still be drivable, it is important to address this issue to avoid potential damage to the catalytic converter and ensure optimal engine performance.
Driving with a faulty oxygen sensor can lead to increased emissions, which may not comply with local environmental regulations.
• Engine at operating temperature
• Vehicle idling in park
The oxygen sensor is located in the exhaust manifold or exhaust pipe before the catalytic converter on Bank 1.
Q: Can I drive with a P2239 code?
A: It's possible to drive, but it's not recommended as it can lead to poor fuel economy and potential damage to the catalytic converter.
Q: How can I prevent oxygen sensor issues?
A: Regular maintenance and using quality fuel can help prevent sensor issues.
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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.