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 a sensor in your car isn't detecting the right temperature change in a part that helps clean the air from your car's exhaust.
The P143E code is triggered when the temperature sensor for the Direct Ozone Reduction Catalyst detects a temperature gradient that is too low, indicating a potential issue with the catalyst's operation.
The Direct Ozone Reduction Catalyst is part of the vehicle's emission control system. It helps reduce ozone emissions by converting them into less harmful substances. The temperature sensor monitors the catalyst's temperature to ensure it is operating efficiently. A low temperature gradient suggests the catalyst may not be functioning properly, possibly due to a sensor issue or catalyst degradation.
• Check Engine Light illuminated
• Possible decrease in fuel efficiency
• Failed emissions test
• Faulty temperature sensor
• Wiring issues or poor electrical connections
• Degraded or damaged catalyst
Catalyst: A substance that increases the rate of a chemical reaction without itself undergoing any permanent chemical change.
Gradient: A rate of inclination; a slope.
• Use an OBD-II scanner to confirm the code.
• Inspect the temperature sensor and wiring for damage.
• Check the catalyst for signs of degradation or damage.
• Replace the faulty temperature sensor.
• Repair or replace damaged wiring or connectors.
• Replace the Direct Ozone Reduction Catalyst if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$200 - $800
Moderate
• Toyota Prius
• Honda Civic Hybrid
• Chevrolet Volt
• Regular maintenance and inspections
• Ensure proper electrical connections
• Use high-quality fuel to prevent catalyst damage
Sensor Issue
• Have a professional diagnose the issue to avoid unnecessary repairs.
• Do not ignore the Check Engine Light as it may lead to more severe problems.
Check with your vehicle manufacturer as emission components may be covered under warranty.
This code has become more common as emission standards have become stricter and vehicles have incorporated more complex emission control systems.
Moderate – Addressing this issue can prevent further damage and ensure your vehicle passes emissions tests.
Driving with a faulty emission control system may violate environmental regulations and lead to fines.
• Engine at operating temperature
• Vehicle running at various speeds
The Direct Ozone Reduction Catalyst is typically located in the exhaust system, near the catalytic converter.
Q: Can I drive my car with a P143E code?
A: While you can drive with this code, it is not recommended as it may lead to further damage and emissions issues.
Q: How do I know if my catalyst is damaged?
A: Signs of a damaged catalyst include a decrease in fuel efficiency, a sulfur smell from the exhaust, and a failed emissions test.
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Helpful when the code points toward exhaust or oxygen-sensor work and space is tight.
Useful when the diagnosis points toward oxygen-sensor removal or replacement.
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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.