P0428 Catalytic converter temperature sensor circuit high (bank 1, sensor 1)

P0428 – OBD-II Trouble Code Technical Description

Trouble code P0428 indicates the catalytic converter temperature sensor (bank 1, sensor 1) signal is high.

What does the fault code mean P0428?

Trouble code P0428 indicates that the catalytic converter temperature sensor (bank 1, sensor 1) signal level is too high. This means that the engine control module (PCM) is receiving a high resolution signal from the catalytic converter temperature sensor that is higher than expected. The catalytic converter in a car is responsible for treating exhaust gases, and its temperature must be within certain limits for the engine management system to function properly.

Possible reasons

Some of the possible causes of the P0428 trouble code are:

• Malfunction of the catalytic converter temperature sensor: The sensor itself may be damaged or have incorrect readings due to wear or corrosion.
• Electrical circuit problems: The wiring connecting the catalytic converter temperature sensor to the engine control module (PCM) may be damaged, broken, or have poor connections, causing erroneous signals.
• Malfunction in PCM: Problems with the engine control module itself, which is responsible for processing signals from the catalytic converter temperature sensor, can cause the P0428 code to appear.
• Malfunctioning catalytic converter: Problems with the catalytic converter itself, such as contamination, damage, or wear, can cause incorrect temperature sensor readings and trouble code P0428.
• Problems with the fuel injection system: Improper operation of the fuel injection system can affect the temperature of the catalytic converter and cause the P0428 code.
• Malfunctions in the ignition system: Improper operation of the ignition system can also result in incorrect catalytic converter temperature and a P0428 code.

To accurately determine the cause, it is necessary to diagnose the vehicle using a diagnostic scanner and analyze engine operating parameters.

What are the symptoms of trouble code P0428?

Symptoms for trouble code P0428 can vary depending on the specific vehicle and the extent of the problem, some of the possible symptoms are:

• Check Engine light on: Typically, when P0428 appears, the Check Engine Light or MIL (Malfunction Indicator Lamp) will illuminate on your vehicle's dashboard, indicating there is a problem with the engine management system.
• Loss of power: Some drivers may notice a loss of engine power or less responsive performance when this error is activated.
• Increased fuel consumption: Malfunctioning catalytic converter due to problems with its temperature sensor can lead to increased fuel consumption due to inefficient use of fuel.
• Unstable engine operation: Problems with idle smoothness or other abnormal engine performance may occur.
• Custom exhaust: If there is a serious problem with the catalytic converter or its temperature sensor, unusual exhaust gases or odors may occur.

The presence or absence of symptoms may depend on the specific operating conditions of the vehicle, its design, and how severe the problem causing the P0428 code is.

How to diagnose a fault code P0428?

To diagnose DTC P0428, you can perform the following steps:

1. Checking Error Codes: First, connect the diagnostic scanner to the OBD-II port and read the error codes. If a P0428 code is detected, it indicates a problem with the catalytic converter temperature sensor.
2. Visual inspection: Check the wiring and connectors connecting the catalytic converter temperature sensor to the engine control module (PCM). Make sure the wiring is not damaged, broken or oxidized.
3. Temperature sensor test: Use a multimeter to check the resistance of the catalytic converter temperature sensor. Make sure the resistance meets the manufacturer's specifications.
4. Check PCM: Perform additional diagnostics to ensure the PCM is correctly reading and responding to the signal from the catalytic converter temperature sensor.
5. Checking the catalytic converter: Check the condition of the catalytic converter itself. It must be free from damage, blockage or wear. If necessary, replace it.
6. Additional tests: Perform additional tests to rule out possible problems with other components, such as the ignition system or fuel injection system.

Diagnostic errors

When diagnosing DTC P0428, the following errors may occur:

• Incomplete diagnosis: Not performing a complete diagnosis may result in missing potential causes of the error. All components related to the catalytic converter temperature sensor as well as the engine management system must be carefully inspected.
• Misinterpretation of data: Incorrect understanding or interpretation of the data provided by the diagnostic scanner can lead to erroneous conclusions about the causes of the P0428 code.
• Wrong solution to the problem: The cause of error P0428 cannot always be clearly detected during the initial diagnosis. Some components may require additional inspection or additional tests to accurately identify the problem.
• Lack of experience or qualificationsNote: Diagnosing a P0428 code may require specific knowledge and experience with engine management and exhaust systems. Insufficient experience or qualifications may lead to incorrect decisions or incorrect identification of the cause of the problem.
• Ignoring additional problems: In some cases, the problem causing the P0428 code may be related to other problems in the exhaust system or engine. Ignoring these additional problems may result in the error reoccurring after repair.

To successfully diagnose and repair error code P0428, it is recommended to use the correct equipment and follow diagnostic procedures.

How serious is the fault code? P0428?

Trouble code P0428 may be considered serious depending on the specific circumstances. Several factors that can influence the severity of this error:

• Potential environmental consequences: Problems with the catalytic converter temperature sensor can cause the unit to not operate properly, which could impair the vehicle's environmental performance and cause it to exceed emissions limits.
• Increased fuel consumption and loss of performance: Malfunctioning catalytic converter due to temperature sensor problems can result in increased fuel consumption and loss of engine performance.
• Potential damage to other components: If the cause of the P0428 code is not corrected, further damage to the exhaust system or other engine components may result.
• Increased risk of refusal to pass a technical inspectionNote: Depending on the country and region, a vehicle with an activated Check Engine Light may not pass inspection, which may result in fines or restrictions on the use of the vehicle.

Based on the above factors, it can be said that the P0428 trouble code should be taken seriously and should be resolved as soon as possible to avoid negative consequences for the vehicle and the environment

What repair will help eliminate the code? P0428?

Resolving trouble code P0428 may require several possible actions, depending on the specific cause of the error, some of them are:

1. Replacing the catalytic converter temperature sensor: If the catalytic converter temperature sensor is identified as the cause of the P0428 code, it should be replaced with a new, working sensor. After replacement, it is recommended to reset the error code using a diagnostic scanner.
2. Repair or replacement of wiring: If wiring problems are found, they should be repaired or replaced to ensure proper signal transmission between the catalytic converter temperature sensor and the engine control module.
3. PCM Check and Repair: If the problem is with the PCM, additional diagnostics must be performed to determine the problem and the PCM must be repaired or replaced as necessary.
4. Checking and replacing the catalytic converter: If the catalytic converter has problems such as damage or wear, it should be replaced. Improper operation of the converter can cause incorrect temperature sensor readings and code P0428.
5. PCM Software Update: Sometimes the problem may be due to bugs in the PCM software. In this case, the PCM may need to be updated or reprogrammed.

It is important to diagnose using the correct equipment and, if necessary, seek help from a professional or mechanic with experience working with engine management systems.

P0428 Catalyst Temperature Sensor High (Bank 1, Sensor 1) 🟢 Trouble Code Symptoms Causes Solutions

P0428 – Brand-specific information

Specific definitions of the P0428 trouble code may vary depending on the vehicle manufacturer, meanings for some brands:

1. Toyota / Lexus:
   • P0428: Catalyst Temperature Sensor High Input (Bank 1)
2. Ford:
   • P0428: Catalyst Temperature Sensor High Input (Bank 1)
3. Chevrolet / GM:
   • P0428: Catalyst Temperature Sensor High Input (Bank 1)
4. Honda/Acura:
   • P0428: Catalyst Temperature Sensor (Bank 1) High Voltage Catalyst Temperature Sensor (Bank 1) high voltage.
5. Nissan/Infiniti:
   • P0428: Catalyst Temperature Sensor High Input (Bank 1)
6. Subaru:
   • P0428: Catalyst Temperature Sensor (Bank 1) High Voltage Catalyst Temperature Sensor (Bank 1) high voltage.
7. Volkswagen/Audi:
   • P0428: Catalyst Temperature Sensor High Input (Bank 1)
8. BMW:
   • P0428: Catalyst Temperature Sensor High Input (Bank 1)
9. Mercedes-Benz:
   • P0428: Catalyst Temperature Sensor High Input (Bank 1)
10. Hyundai/Kia:
    • P0428: Catalyst Temperature Sensor (Bank 1) High Voltage Catalyst Temperature Sensor (Bank 1) high voltage.

These transcripts indicate problems with a high signal level of the catalytic converter temperature sensor in bank 1 in various makes of cars.