Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
Your car has a sensor that measures how hot the exhaust is. This code means that the sensor is saying the temperature is colder than it should be.
The code P242C indicates that the signal from the exhaust gas temperature sensor on bank 1, sensor 3, is lower than expected. This sensor helps the car's computer know how hot the exhaust gases are.
The Exhaust Gas Temperature (EGT) Sensor measures the temperature of the exhaust gases leaving the engine. This information is used by the engine control module (ECM) to optimize engine performance and emissions. Code P242C is triggered when the ECM detects a voltage signal from the EGT sensor that is lower than the specified range, indicating a possible issue with the sensor or its circuit.
• Check Engine Light is on
• Poor fuel economy
• Possible decrease in engine performance
• Faulty exhaust gas temperature sensor
• Wiring issues such as shorts or open circuits
• Corroded or damaged connectors
Exhaust Gas Temperature (EGT) Sensor: A sensor that measures the temperature of the exhaust gases.
Bank 1: The side of the engine with cylinder 1, typically the driver's side in a V-type engine.
• Use an OBD-II scanner to confirm the code.
• Inspect the EGT sensor and its wiring for damage.
• Test the sensor's resistance and compare it to the manufacturer's specifications.
• Replace the faulty exhaust gas temperature sensor.
• Repair or replace damaged wiring or connectors.
• Clear the code and test drive the vehicle to ensure the issue is resolved.
• OBD-II scanner
• Multimeter
• Basic hand tools
$100 - $300
Moderate
• Ford F-150
• Chevrolet Silverado
• Dodge Ram
• Regularly inspect and maintain exhaust system components.
• Ensure proper electrical connections and wiring integrity.
• Use high-quality fuel to prevent sensor contamination.
Sensor Issue
• Do not ignore the Check Engine Light.
• Have the vehicle inspected by a professional if unsure.
• Regular maintenance can prevent such issues.
Sensor-related issues may be covered under the vehicle's emissions warranty.
Exhaust gas temperature sensors have been used in vehicles for emissions control and engine performance optimization for many years.
Moderate – While the vehicle may still be drivable, ignoring this issue can lead to decreased fuel efficiency and potential damage to the catalytic converter.
Driving with a malfunctioning exhaust gas temperature sensor may lead to increased emissions, which can be a violation of local emissions laws.
• Engine at operating temperature
• Vehicle idling or under load
The exhaust gas temperature sensor is typically located in the exhaust manifold or near the catalytic converter on bank 1.
Q: Can I drive my car with code P242C?
A: You may be able to drive, but it's best to get it checked soon to avoid further issues.
Q: How do I reset the Check Engine Light after fixing the issue?
A: Use an OBD-II scanner to clear the code, or disconnect the battery for a few minutes.
High-End · Full-system diagnostics
A full-system bidirectional platform aimed at advanced DIY users and professional diagnostic workflows.
Network faults often require full-system access instead of a generic code reader alone.
View on Amazon
Universal · Digital multimeter
A solid entry-level multimeter for voltage, continuity, resistance, and basic electrical troubleshooting.
Helpful for checking voltage drops, grounds, and basic circuit health when modules are not communicating.
View on Amazon
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.
View on AmazonThese are optional diagnostic tools, not guaranteed fixes. As an Amazon Associate I earn from qualifying purchases.
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.