Dtc p0420 kia

The logic on how these codes are generated is this. Exhaust gases exit the engine. The upper 02 Sensor ( You have 4 Total, Two Upper and Two Lower ) Reads the exhaust gases coming out of the engine. Then rear 02 Sensor reads the exhaust gases. If converted properly, the rear 02 sensor will have nothing to read.

Dtc p0420 kia. Diagnostic trouble code(DTC) P200A stands for “Intake Manifold Runner Performance (Bank 1).”. This code is logged when the powertrain control module (PCM) has detected a problem with the intake manifold runner control (IMRC) system. This code is also logged when the intake manifold runnerdoes not operate as it should.

P0420 Diagnosis: Kia Sportage. The most common fix for P0420 in the Kia Sportage is a new catalytic converter, followed by an O2 sensor replacement. Before taking your Sportage into an exhaust shop for an (expensive) new catalytic converter, let’s ensure that’s what you need.

This page is meant to help you troubleshoot the Kia Rondo P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table of ContentsOn other vehicles, an exhaust leak could manifest itself as a diagnostic trouble code (DTC) for the Air-fuel ratio sensor (i.e., the upstream O2 sensor). Kia Soul 2015 2.0 litre EX GDI Alien Green II Pearl ~73K km (45K miles) Michelin CrossClimate tires/nwsys/www/images/PBC_1251019 Research Announcement: Vollständigen Artikel bei Moodys lesen Indices Commodities Currencies Stocks23 Feb 2022 ... HYUNDAI KIA CODE P2196 P2271 O2 SENSOR STUCK RICH OXYGEN SENSOR If you have Hyundai or Kia and you have engine light and code P2196 P2271 O2 ...Kia revealed Tuesday the next EV in its portfolio, a three-row flagship SUV called the EV9 that is packed with tech and a key product in the company's mission to reach annual sales...

Yes, partially; the Hyundai Motor Company owns about a third of Kia Motors. Both Kia and Hyundai are large automobile makers originally based in South Korea. Hyundai is the largest...P0420 has been coming up regularly for 6-8 months now, and my front cat finally plugged up this week. $1,400 CAD for the parts only, but if I had set the parts aside ahead of time from Rock Auto, I would have paid about $1,000 in total for these items. Labor was another 3.5 hours to replace everything.The E8 and E9 represent different modules or parts of the vehicle from where the codes are retrieved. E8 represents the engine control module while E9 represents the transmission control module. In short: 7E8 means a request code from ECM. 7E9 means a request from TCM. After inputting the codes a request will be sent and you’ll get a …waddy said: 2015 Soul, 1.6 L, V4 - 93,000 + mi. Code P0420 Catalyst operating below minimum threshold. P0420 is an all around code dealing with emmisions. To learn more about this code, view YouTube videos of scannerdanner. or any other videos explaining about 02 sensors, fuel trims, catalytic converter, etc.Two companies are denying coverage for these Kia and Hyundai vehicles because they're so easily hot-wired. Car insurance companies don’t take unnecessary risks—and now, for State F...

This page is meant to help you troubleshoot the Kia Rondo P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table of ContentsOne of the most frequent diagnostic trouble codes (DTCs) that car owners see is P0420. It means that Bank 1’s catalytic converter performance on Bank 1 has been identified by the engine control module (ECM). The catalyst may be at fault for this code, or an O2 sensor may be to blame for a false alert. Understanding the significance of the ...P0420 KIA - Código DTC de falla OBD2; P0420 Volkswagen - Código DTC de falla OBD2; Síntomas del código OBD2 P0420 Honda. Los signos de un código de falla P0420 Honda pueden incluir: Reducción de la potencia del motor; Aumento en el consumo de combustible; Olor a huevos podridos en el escape;Medicine Matters Sharing successes, challenges and daily happenings in the Department of Medicine ARTICLE: Gastric per-oral endoscopic myotomy (G-POEM) for refractory gastroparesis...Medicine Matters Sharing successes, challenges and daily happenings in the Department of Medicine ARTICLE: Gastric per-oral endoscopic myotomy (G-POEM) for refractory gastroparesis...

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To diagnose the P0456 KIA code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.If the OBD-II code reader displays a P0420 or P0430 trouble code, bring your vehicle to an auto repair shop for a thorough checkup and repair job.. How the Catalytic Converter Works. The catalytic converter is …The DTC number is a number that is issued in connection with Depository Trust Company transactions. The number, known as an International Securities Identification Number, or ISIN,...The P0420 code is a diagnostic trouble code that indicates a problem with the catalytic converter efficiency in a Kia Sorento. When this code appears, it means that the catalytic converter is not functioning optimally, resulting in higher emissions. 2. Common Causes of the P0420 code in Kia Sorento.Se trata de un código que indica una disminución en la eficiencia del sistema de catalizador, encargado de reducir las emisiones contaminantes del vehículo. En nuestro escaner automotriz nos aparecerá con alguno de los siguientes nombres: P0420. Eficiencia del sistema catalítico por debajo del umbral. P0420.The P0420 code indicates that the Engine Control Module (ECM) has identified a decline in the efficiency of the catalytic converter on Bank 1. This could be attributed to a malfunctioning catalyst or potentially be a false alarm triggered by a defective O2 sensor. The engine control module (ECM) uses two O2 sensors, one in front, and one behind ...

P0420 code. I have a 2016 Kia Soul 1.6L, we have had a run around with Kia over these codes. We first had the Knock Sensor put in and after that the engine light would come on and off from time to time. We contacted the Kia dealer we purchased it from and spoke with the maintenance dept manager. He said that when the seasons change that it ...P050A and secondary P0420. I own a 2014 1.6 base model with a little less than 100k in it. Was have P050A code come on in cold weather with high idle at start but then recently took it to kia to get logic update. That fixed the problem of high idle but then randomly the check engine light will come on for a couple days then go off again for a ...What Causes the Catalytic Converter to Fail. How To Diagnose Trouble Code P0420: Catalyst Efficiency Below Threshold (Bank 1). TEST 1: Checking For a Broken Catalytic Converter. TEST 2: Checking The Output Of The Rear Oxygen Sensor. TEST 3: Manually Inducing A Lean Condition.How To Fix The P0420 Trouble Code. Verify the code with an OBD-II scanner and reset the check engine light to see if it comes back. Inspect and replace faulty oxygen sensors. Check for exhaust leaks and repair as necessary. Replace worn-out spark plugs or spark plug wires.Kia revealed Tuesday the next EV in its portfolio, a three-row flagship SUV called the EV9 that is packed with tech and a key product in the company's mission to reach annual sales...Nov 12, 2018 · This page is meant to help you troubleshoot the Kia Rio P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table of Contents. Quick ... There are several potential causes for the P0420 code in a 2015 Kia Soul. Some common causes include a faulty catalytic converter, oxygen sensor issues, exhaust leaks, engine misfires, or a malfunctioning fuel control system. It is important to diagnose the specific cause of the code in order to efficiently resolve the issue.P0420: význam, příčiny, opravy. Význam kódu P0420. Chybový kód P0420 indikuje, že katalyzátor nepracuje účinně, a obvykle i to, že je nutné ho vyměnit. Pokud se objeví, nutné bude provést diagnostiku motoru, a diagnostiku systému vstřikování paliva, zapalování, a výfukového systému. Příčiny P0420.Code: P0420. System: Powertrain (Covers functions that include engine, transmission and associated drivetrain accessories) Category: ISO/SAE (It is core DTCs and applied to most manufacturers. A common fault message is assigned to this code.) Component: Auxiliary emission controls.2. Sensor de oxígeno defectuoso. Otra razón por la que puedes obtener un código P0420 es por un sensor de oxígeno defectuoso. Esto sucede con menos frecuencia, pero a veces, los sensores de O2 pueden fallar y causar todo tipo de problemas. Eso es incluso si continúan funcionando y no recibes errores de ellos.The P0430 trouble code is considered generic, meaning it occurs on vehicles of any type and model. The P0430 shows a problem with the emissions system. It is exactly the same as P0420 DTC, with the only difference being that that one refers to the oxygen sensors on bank 1 instead. These codes illustrate two different sides of the engine.

P0420 Possible Symptoms. P0420 is not always noticeable except the engine light/service engine soon warning light. Sometimes, you can feel the lack of power from the engine and decreased fuel economy. Engine Light ON (or Service Engine Soon Warning Light) Lack of power from the engine. Decreased fuel economy. Rotten egg or a sulfur …

Code Search and confirm DTC P0420 or both P0420 and P030X is/are stored (Active, ... Before attempting an ECU upgrade on any Kia model, make sure to first determine whether the particular model is equipped with an immobilizer security system. Failure to follow proper procedures may cause the PCM to become inoperative after the upgrade and any ...Issue: Some 2013-2018 Police Interceptor Utility vehicles equipped with a 3.7L Twin independent-Variable Camshaft Timing (Ti-VCT) engine may exhibit an illuminated MIL with DTC P0420 and/or P0430. Action: Follow the Service Procedure steps to correct the condition.Aug 22, 2018 · Te suministramos todo lo que necesitas saber sobre el código DTC P0420: ️ Descripción, ️ causas, ️ síntomas y ️ posibles soluciones.LEER SOLUCIÓN DEL CÓD... Código P0420: síntomas. Código P0420: significado, síntomas, causas (soluciones fáciles) Activación de la luz de verificación del motor en el tablero. Fallas en el encendido. Gran consumo de combustible. Desagradable olor que sale del tubo de escape.What does catalyst efficiency below threshold (bank 1) mean on 03 kia spectra? - Answered by a verified Kia Mechanic ... the P0420 is set. As long as there are no leaks in the exhaust system, the converter is going to need to be replaced. Ron Z. Category: Kia. Satisfied Customers: 26,515. Experience: 18+yrs experience. State …This page is meant to help you troubleshoot the Kia Rio P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table of Contents. Quick ...This page is meant to help you troubleshoot the Kia Rondo P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table …

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Code P0420 "catalyst system efficiency below threshold." Local Kia dealer's first available slot for a diagnostic appointment is one week from now; they charge $90.00 to diagnose the problem; they say there's a 8-year 80,000 mile warranty on the catalytic converter. Any thoughts? Suggestions? Tips? Thanks for your help! 2013 Rio LX 4-Door.This page is meant to help you troubleshoot the Kia Venga P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table …This page is meant to help you troubleshoot the Kia Picanto P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table …Nov 12, 2018 · This page is meant to help you troubleshoot the Kia Rio P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table of Contents. Quick ... P0303 is a cylinder-specific misfire code, meaning it’s only the third cylinder that has a misfire. Before you can diagnose P0303 in your car, you need to find the third cylinder. On “V” configuration engines, it’ll usually be the second cylinder on the head closer to the front of the engine. On inline engines, the third cylinder will ...Step 1: Check for other trouble codes. Before focusing solely on the P0420 code, it is essential to check for any additional trouble codes that may provide clues about the underlying issue. These codes could indicate problems unrelated to the catalytic converter. Step 2: Inspect the catalytic converter.Code: P0420. System: Powertrain (Covers functions that include engine, transmission and associated drivetrain accessories) Category: ISO/SAE (It is core DTCs and applied to most manufacturers. A common fault message is assigned to this code.) Component: Auxiliary emission controls.Here’s a good P0420 diagnostic order for the Hyundai Genesis: 1. Check for Other Codes. The first thing you want to do when trying to fix P0420 in the Genesis is to verify there aren’t any other trouble codes. Three types of codes can give clues as to what’s going on with your car. Misfire Codes.What Does the P054A Code Mean? Diagnostic trouble code (DTC) P054A stands for “Cold Start B Camshaft Position Timing Over-Advanced Bank 1.” The code is set once the powertrain control module (PCM) detects that the camshaft timing extremely varies from what it should be.. Between the camshafts and their driving sprockets are hydraulic …Even slight variations in the air/fuel mixture will cause the converter temperature to rise significantly. The “Catalytic Converter Efficiency” Diagnostic Trouble Codes (DTCs) P0420 and P0430, are among the top 10 DTCs technicians face. And while the description might imply a failed converter, odds are the ultimate fault lies somewhere else. ….

22 Jan 2018 ... ... P0420 or P0430 code. These are your catalytic converter efficiency codes. By installing a spark plug non fouler with a drilled hole you can ... Hablamos sobre el codigo de falla dtc p0420, que lo hace activar y como se soluciona. OBD2 고장코드 (DTC) P0420 임계값 이하의 촉매 시스템 효율성 (뱅크1) OBD2 규격 (SAE J2012)에 따라 실제 적용한 제조사별 고장코드의 의미는 다음과 같습니다. 현대 (HYUNDAI) DTC 24 운전석 사이드 인플레이트 저항낮음. 현대 (HYUNDAI) DTC P0420 뱅크1 촉매시스템 효율낮음.This page is meant to help you troubleshoot the Kia Rondo P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table of ContentsHere are some steps to fix a P0420 code Honda Accord. First, remove the O2 sensor and pour 4-6 ounces of seafoam into the opening, replace the sensor, and leave it overnight. Reset the code and then continue driving. Increase the gap between the oxygen sensor and the converter using a spark plug non-fowler.412. PS GAMMA 1.6GDI ECU MIL ON DTC (P0420) LOGIC IMPROVEMENT 413. AM GAMMA 1.6GDI ECU MIL ON DTC (P0420) LOGIC IMPROVEMENT A fully charged battery is necessary before ECU upgrade can take place. It is recommended that the Midtronics GR8-1299 system be used in ECU mode during charging.In this video, you'll learn the causes and solutions of the P0420 code. The causes of the P0420 code are a bad catalytic converter, an ECM update, an exhaust...23 Feb 2022 ... HYUNDAI KIA CODE P2195 P2270 O2 SENSOR STUCK LEAN OXYGEN SENSOR If you ... CHEAP Catalytic Converter Fix - P0420 P0430 ... DTC P2270 Overview: O2 ...DTC P0213: Cold Start Injector 1; DTC P0214: Cold Start Injector 2; Help Us Help You. Please comment below describing your issue as well as the specifics of your vehicle (make, model, year, miles, and engine). To get a detailed, expedited response from a mechanic, please make a $9.99 donation via the payment button below.This page is meant to help you troubleshoot the Kia Rondo P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table … Dtc p0420 kia, P0420 trouble code. Jump to Latest Follow. 10K views 9 replies 5 participants last post by sadiem15 Mar 6, 2024. Windsor Discussion starter. 87 posts · …, Can you rent a car from a dealership? We explain which car dealerships rent cars, including Ford, Toyota, and more. Details inside. Most car dealerships are individually owned and ..., One of the most common catalytic converter codes your vehicle will throw at you is the P0420 (not to be mistaken with trouble code P0430). This diagnostic trouble code (DTC) stands for "Catalyst System Below Efficiency", coming from the bank 1 mounting position., Faraday Future will discuss plans to finally build its FF91 car on Dec. 15 and FFIE stock rose on the hope of hearing something positive. Faraday Future will describe its future at..., Diagnostic trouble code (DTC) P0463 stands for “Fuel Level Sensor “A” Circuit High.”. It means that there is an unusually high voltage signal coming from your vehicle’s fuel sensor. The result is that the fuel gaugewill not read accurately. Note:Although code P0463 is a generic code specified by the Society of Automotive Engineers ..., P0420: význam, příčiny, opravy. Význam kódu P0420. Chybový kód P0420 indikuje, že katalyzátor nepracuje účinně, a obvykle i to, že je nutné ho vyměnit. Pokud se objeví, nutné bude provést diagnostiku motoru, a diagnostiku systému vstřikování paliva, zapalování, a výfukového systému. Příčiny P0420., P0320 definition: Ignition/Distributor Engine Speed input circuit has a malfunction. Issue Severity: MODERATE – Extended driving with this code may cause internal engine damage. Repair Urgency: Get this code fixed as soon as possible to avoid being stuck with an engine that won’t start. Diagnosis: This trouble code can have no …, When the P0420 code appears, the catalyst system efficiency is below the threshold for a particular engine bank, often referred to as Bank 1. This code is related to the vehicle's catalytic converter and oxygen sensors. The primary purpose of a catalytic converter is to reduce harmful emissions from the engine by converting toxic gasses, such ..., Se trata de un código que indica una disminución en la eficiencia del sistema de catalizador, encargado de reducir las emisiones contaminantes del vehículo. En nuestro escaner automotriz nos aparecerá con alguno de los siguientes nombres: P0420. Eficiencia del sistema catalítico por debajo del umbral. P0420., HI ALL I need to remove a dtc from kia ceed 2012 1.6D . ECU: BOSCH ME17.9.11 DTC: P0420 BEST REGARDS. ... WinOLS (Kia Ceed (Version 1) dtc p0420.rar. 6 307.57 KB ..., P0420 has been coming up regularly for 6-8 months now, and my front cat finally plugged up this week. $1,400 CAD for the parts only, but if I had set the parts aside ahead of time from Rock Auto, I would have paid about $1,000 in total for these items. Labor was another 3.5 hours to replace everything., My car is showing a P0420 code with CEL on the dash and while I was doing some research as to the possible causes and what not it was saying that the most common cause is the upstream O2 sensor and I can test it but I guess my question would be is there a certain ohm range that The multimeter would have to register to know whether it’s good or bad?, Sep 26, 2022 · A P0420 code is set when the upstream sensor and the downstream oxygen sensor sense the catalytic converter is not doing its job. Basically, the amount of oxygen going into the converter is not being burned, and it detects it through the downstream sensor. Oxygen is the key here. Modern Engine Management Systems leave a little bit of extra ... , Dec 27, 2022 · P0420 definition : Catalyst system efficiency below threshold (Bank 1) Issue Severity: MODERATE – Extended driving with this code can cause internal engine damage. Repair Urgency: Get this code fixed as soon as possible to avoid further damage to your emission system and possible engine damage. Diagnosis: The most common cause of P0420 is a ... , This page is meant to help you troubleshoot the Kia Rondo P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table of Contents, 10 Oct 2021 ... 7:07. Go to channel · Can Cataclean really fix a catalytic converter / P0420 / P0430 error code. Mountain Man Mo•550K views · 4:46. Go to ..., Medicine Matters Sharing successes, challenges and daily happenings in the Department of Medicine ARTICLE: Gastric per-oral endoscopic myotomy (G-POEM) for refractory gastroparesis..., This page is meant to help you troubleshoot the Kia Telluride P0420 trouble code. It covers the P0420 code’s meaning, symptoms, causes, and possible solutions. P0420 is the most common OBDII code and is virtually never a breakdown risk. A failing oxygen sensor or bad catalytic converter are the most common causes of P0420. Table …, The 2023 Kia Telluride is an exciting new SUV that is sure to turn heads. It is the perfect combination of style, luxury, and performance. Here’s what you need to know about the 20..., The stock market is awaiting the next macroeconomic catalyst, writes James "Rev Shark" DePorre, who says unemployment reports are on deck, and then the next Fed r..., The code P0300 indicates there are repetitive misfires on one or more cylinders in your car. You will often find this code together with another code of the specific cylinder the misfire occurred on. If the last digit of the trouble code is not zero, e.g., if the generated code is P0302, the number 2 indicates that cylinder number 2 has a misfire., Diagnostic trouble code (DTC) P0420 stands for “P0420 Catalyst System Efficiency Below Threshold (Bank 1).” It indicates that the exhaust system’s oxygen levels are below the required threshold in Bank 1, which can damage the engine’s exhaust and fuel system., Here are some steps to fix a P0420 code Honda Accord. First, remove the O2 sensor and pour 4-6 ounces of seafoam into the opening, replace the sensor, and leave it overnight. Reset the code and then continue driving. Increase the gap between the oxygen sensor and the converter using a spark plug non-fowler., El código de diagnóstico P0420 DTC de KIA se refiere a un problema en el convertidor catalítico del vehículo. El convertidor catalítico es una parte esencial del sistema de escape de un automóvil y su función principal es reducir las emisiones de CO y hidrocarburos. El Módulo de Control del Tren de Potencia (PCM) del vehículo compara ..., =====Claim your FREE engine code eraser 👉 https://free.nonda.co 👈=====Engine Code P0420 Saving Repair Parts:C... , Kia Spectra P0449 Definition. P0449 is a universal OBDII trouble code. This means that regardless of which make or model of vehicle, the code will mean the same thing (Spectra or not, as long as it was manufactured after 1996). P0449 indicates that the valve or solenoid circuit that controls the evaporation system is not functioning properly., Here is a tutorial on how to fix code p0420 catalyst system efficiency below threshold bank 1 how to diagnose and fix a Catalytic Converter and what to look ..., This article will therefore deal with code P0420 as it applies specifically to GM vehicles. OBD II fault code P0420 is a generic trouble code that is defined as “Catalytic converter system, bank 1 – efficiency below threshold” and is set when the PCM (Powertrain Control Module) detects a condition in which the efficiency of the catalytic ..., Jan 5, 2024 · When the P0420 code appears, the catalyst system efficiency is below the threshold for a particular engine bank, often referred to as Bank 1. This code is related to the vehicle's catalytic converter and oxygen sensors. The primary purpose of a catalytic converter is to reduce harmful emissions from the engine by converting toxic gasses, such ... , addressing the P0420 DTC. Important: The ECM and Transmission Control Module (TCM) must be reprogrammed simultaneously. • After ECM calibration has finished, the system will request to verify TCM calibration is up-to-date. Make sure that the TCM contains the latest software. • If the TCM is not up-to-date, refer toControl, OBD2 고장코드 (DTC) P0420 임계값 이하의 촉매 시스템 효율성 (뱅크1) OBD2 규격 (SAE J2012)에 따라 실제 적용한 제조사별 고장코드의 의미는 다음과 같습니다. 현대 (HYUNDAI) DTC 24 운전석 사이드 인플레이트 저항낮음. 현대 (HYUNDAI) DTC P0420 뱅크1 촉매시스템 효율낮음., If the efficiency is lower than it should be, the ECU will store OBD-II code P0420. The definition of the OBD-II P0420 code is “ Catalyst System Efficiency Below Threshold (Bank 1) ”. When the ECU stores this code, it means that the catalytic converter is not operating at maximum efficiency and may need replacement. Car fault code: P0420., A code P0420 may mean that one or more of the following has happened: Leaded fuel was used where unleaded was called for (unlikely) A damaged or failed oxygen / O2 sensor. Downstream oxygen sensor (HO2S) wiring damaged or connected improperly. The engine coolant temperature sensor is not working properly.