SUMMER SALE!

| DTC Code | Standard Error Message | Possible Causes |
|---|---|---|
| P0010 – Meaning, Causes, Symptoms, & Fixes | Intake Camshaft Actuator Circuit Open/Short (Bank 1) | Faulty VVT control solenoid valve, Oil sludge in the engine, Crankshaft position sensor malfunction, Camshaft position sensor malfunction, Frayed or damaged wiring, Engine operating outside of proper timing parameters |
| P0020 – Meaning, Causes, Symptoms, & Fixes | Intake Camshaft Actuator Circuit Open/Short (Bank 2) | Faulty VVT control solenoid valve, Oil sludge in the engine, Crankshaft position sensor malfunction, Camshaft position sensor malfunction, Frayed or damaged wiring, Engine operating outside of proper timing parameters |
| P0320 – Meaning, Causes, Symptoms, & Fixes | Ignition/Distributor Engine Speed input circuit has a malfunction | Ignition/distributor engine speed sensor, Camshaft position sensor, Crankshaft position sensor, Weak battery, Dirty or damaged reluctor ring |
| P0021 – Meaning, Causes, Symptoms, & Fixes | Intake Camshaft Position Timing - Over-Advanced (Bank 2) | Engine oil is dirty, Engine oil is too low, Engine oil is incorrect viscosity, Camshaft variable valve timing control solenoid failure, Camshaft phaser is seized in the advanced position, Continuous oil flow to Variable Camshaft Timing chamber |
| P0024 – Meaning, Causes, Symptoms, & Fixes | Exhaust Camshaft Timing- Over-Advanced Bank 2 | Engine oil is dirty, Engine oil is too low, Engine oil is incorrect viscosity, Camshaft variable timing solenoid failure, Camshaft phaser is seized in the advanced position, Continuous oil flow to Variable Camshaft Timing chamber |
| P0014 – Meaning, Causes, Symptoms, & Fixes | Exhaust Camshaft Timing- Over-Advanced Bank 1 | Engine oil is dirty, Engine oil is too low, Engine oil is incorrect viscosity, Camshaft variable timing solenoid failure, Camshaft phaser is seized in the advanced position, Continuous oil flow to Variable Camshaft Timing chamber |
| P0336 – Meaning, Causes, Symptoms, & Fixes | The engine control module, ECM, has detected an improper/irregular voltage coming from the crankshaft position sensor. | Faulty crankshaft position sensor (most common), Damaged reluctor ring, Loose or improperly installed reluctor ring, Chaffed wiring, Poor connection at connector, Open in crankshaft position sensor circuit |
| P0121 – Meaning, Causes, Symptoms, & Fixes | Throttle Position Sensor (TPS) "A" Circuit Range Performance Problem | Faulty Throttle Position Sensor (TPS), Dirty Throttle Body, Faulty Throttle Body, An open or short of the TPS circuit, Bad connection of the TPS connector, Corrosion on terminal ends of electrical connections |
| P0011 Engine Code | “A” Camshaft Position—Timing Over-Advanced (Bank 1) | Intake Camshaft Timing Over-Advanced (Bank 1) | Dirty or low engine oil, Incorrect engine oil viscosity, Faulty camshaft variable timing solenoid, Camshaft phaser stuck in advanced position, Continuous oil flow to the Variable Camshaft Timing (VCT) chamber |
| P0012 – Meaning, Causes, Symptoms, & Fixes | Intake Camshaft Position Timing- Over-Retarded (Bank 1) | Engine oil is too low, Dirty/sludged engine oil, Low oil pressure, Malfunctioning camshaft timing, Short in intake timing control/oil control circuit, Faulty intake valve timing control solenoid, Faulty oil control valve (OCV) |
| P0022 – Meaning, Causes, Symptoms, & Fixes | Intake Camshaft Position – Timing Over-Retarded (Bank 2) | Engine oil too low, Dirty engine oil, Sludged up engine, Low oil pressure, Malfunctioning camshaft timing, Short in intake timing control/oil control circuit, Faulty intake valve timing control solenoid, Faulty oil control valve (OCV) |
| P0016 Engine Code | Camshaft and Crankshaft Not In Sync | Camshaft Position A—Camshaft Position Correlation | Dirty/Low Engine Oil, Faulty Camshaft or Crankshaft Position Sensor, Malfunctioning Camshaft or Crankshaft Reluctor Ring, Defective Timing Belt/Chain |
| P0008 – Meaning, Causes, Symptoms, & Fixes | Engine Position System Performance Bank 1 | Stretched timing chain, Jumped timing, Slipped reluctor ring on the crankshaft, Slipped reluctor ring on bank 1 camshaft, Faulty timing chain tensioner |
| P0009 – Meaning, Causes, Symptoms, & Fixes | Engine Position System Performance Bank 2 | Stretched timing chain, Jumped timing, Slipped reluctor ring on the crankshaft, Slipped reluctor ring on bank 2 camshaft, Faulty timing chain tensioner |
| P0016 Engine Code | Camshaft and Crankshaft Not In Sync | The correlation of the camshaft and crankshaft positions on bank 2 is incorrect based on the intake camshaft position sensor. | Stretched timing chain, Jumped timing, Slipped reluctor ring on the crankshaft, Slipped reluctor ring on bank 2 exhaust camshaft, Faulty timing chain tensioner, Low/dirty oil |
| P0345 – Meaning, Causes, Symptoms, & Fixes | Camshaft Position Sensor Circuit Malfunction | A defective camshaft position sensor, Damaged or dirty reluctor ring on the camshaft, Defective, corroded, shorted camshaft position sensor circuit wiring, Defective, corroded, shorted camshaft position sensor circuit connector, A faulty crankshaft position sensor, Stretched or misaligned timing components, ECM software update needed, Faulty ECM |
| P0340 Engine Code Explained: Causes, Symptoms & How To Fix It | Camshaft Position Sensor Circuit Malfunction | A defective camshaft position sensor, Damaged or dirty reluctor ring on the camshaft, Defective, corroded, shorted camshaft position sensor circuit wiring, Defective, corroded, shorted camshaft position sensor circuit connector, A faulty crankshaft position sensor, Stretched or misaligned timing components, ECM software update needed, Faulty ECM |
| P0335 – Meaning, Causes, Symptoms, & Fixes | Crankshaft Position Sensor "A" Circuit Malfunction (Bank 1) | Damaged or defective crankshaft position sensor, Broken timing belt or chain, Rough running/misfiring engine, Failed ECM |
| DTC Code | Standard Error Message | Possible Causes |
|---|---|---|
| P0031 – Meaning, Causes, Symptoms, & Fixes | HO2S Heater Control Circuit Low (Bank 1, Sensor 1) | Frayed heater circuit wiring/connectors, Faulty heater circuit fuse, Faulty heated oxygen sensor, Malfunctioning PCM/ECM |
| P0037 – Meaning, Causes, Symptoms, & Fixes | H02S2 Heater Control Circuit Low (Bank 1, Sensor 2) | Faulty Bank 2 Oxygen Sensor 2 Heater (Most likely cause), Malfunctioning ECM Sensor Heater Driver, Shorted Control Circuit, A break in wire between ECM and HO2S2, Poor Ground, Blown Fuse |
| P0051 – Meaning, Causes, Symptoms, & Fixes | HO2S Heater Control Circuit Low (Bank 2, Sensor 1) | Frayed heater circuit wiring/connectors, Faulty heater circuit fuse, Faulty heated oxygen sensor, Malfunctioning PCM/ECM |
| P0057 – Meaning, Causes, Symptoms, & Fixes | H02S2 Heater Control Circuit Low (Bank 2, Sensor 2) | Faulty Bank 2 Oxygen Sensor 2 Heater (Most likely cause), Malfunctioning ECM Sensor Heater Driver, Shorted Control Circuit, A break in wire between ECM and HO2S2, Poor Ground, Blown Fuse |
| P0130 – Meaning, Causes, Symptoms, & Fixes | Oxygen Sensor Circuit Malfunction (Bank 1, Sensor 1) | Faulty Bank 1 O2 sensor 1, Exhaust leak in front of sensor 1, Intake leak, Corrosion in connecter, Frayed or broken wiring |
| P0133 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Circuit Low Voltage (Bank 1, Sensor 1) | Faulty oxygen sensor (most common), Short on voltage to O2 circuit, Exhaust leaks, Fuel pressure low, Engine running lean |
| P0133 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Circuit Slow Response (Bank 1 Sensor 1) | Faulty O2 sensor (most common), Faulty/Frayed wiring to the O2 sensor, Exhaust Leak, Engine Vacuum Leak, Dirty Mass Air Flow sensor |
| P0134 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Circuit No Activity Detected (Bank 1, Sensor 1) | Faulty O2 sensor, Faulty heater circuit, A frayed or broken wiring, Poor connection at the O2 sensor connector, Engine Vacuum Leak, Exhaust Leak, Faulty ECM |
| P0135 Engine Code | Oxygen O2 Sensor Heater Circuit Malfunction (Bank 1, Sensor 1) | O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 1) | Faulty Pre-Catalyst oxygen sensor, Faulty wiring/connections, Short or open ground in the wiring, Blown Fuse, Engine coolant temperature sensor is not operating correctly, Faulty Power Control Module |
| P0136 – Meaning, Causes, Symptoms, & Fixes | H02S2 Heater Control Circuit Low (Bank 2, Sensor 2) | Faulty Bank 1 O2 sensor 2, Exhaust leak in front of sensor 2, Intake Leak, Corrosion in connecter, Frayed or broken wiring |
| P0137 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Circuit Low Voltage (Bank 1, Sensor 2) | Faulty oxygen sensor (most common), Short on voltage to O2 circuit, Exhaust leaks, Fuel pressure low, Engine running lean |
| P0138 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Circuit High Voltage (Bank 1, Sensor 2) | Faulty O2 Sensor, Short to battery voltage in O2 sensor signal circuit, Corroded wiring, Fuel pressure too high, Engine coolant temperature sensor |
| P0141 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Heater Circuit Malfunction (Bank 1 Sensor 2) – Downstream | Faulty rear most oxygen sensor, Faulty wiring/connections, Short or open ground in the wiring |
| P0150 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Circuit Malfunction (Bank 2, Sensor 1) | Detected voltages not within normal range, Exhaust leaks in front of sensor, Open or short in circuit, Corrosion/damaged O2 Sensor connector, Frayed wiring/connection to O2 sensor, Intake vacuum air leaks, Faulty O2 sensor |
| P0152 – Meaning, Causes, Symptoms, & Fixes | Bank 2 Sensor 1 oxygen sensor has an abnormally high voltage reading | Bank 2 Sensor 1 O2 Sensor (most common), Vehicle running rich (possible codes P0172 and/or P0175), Frayed, damaged, or shorted wiring, Faulty connector(s), Stuck open or leaking fuel injector, Faulty fuel pressure regulator |
| P0153 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Circuit Slow Response (Bank 2 Sensor 1) | Faulty O2 sensor (most common), Faulty/Frayed wiring to the O2 sensor, Exhaust Leak, Engine Vacuum Leak, Dirty Mass Air Flow sensor |
| P0154 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Circuit No Activity Detected (Bank 2, Sensor 1) | Faulty O2 sensor, Faulty heater circuit, A frayed or broken wiring, Poor connection at the O2 sensor connector, Engine Vacuum Leak, Exhaust Leak, Faulty ECM |
| P0155 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 1) | Faulty Pre-Catalyst oxygen sensor, Faulty wiring/connections, Short or open ground in the wiring, Blown Fuse, Engine coolant temperature sensor is not operating correctly, Faulty Power Control Module |
| P0156 – Meaning, Causes, Symptoms, & Fixes | Oxygen Sensor Circuit Malfunction (Bank 2, Sensor 2) | Faulty Bank 2 O2 sensor 2, Exhaust leak in front of sensor 2, Intake leak, Corrosion in connecter, Frayed or broken wiring |
| P0157 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Circuit Low Voltage (Bank 2, Sensor 2) | Faulty oxygen sensor (most common), Short on voltage to O2 circuit, Exhaust leaks, Fuel pressure low, Engine running lean |
| P0158 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Circuit High Voltage (Bank 2, Sensor 2) | Faulty O2 Sensor, Short to battery voltage in O2 sensor signal circuit, Corroded wiring, Fuel pressure too high, Engine coolant temperature sensor |
| P0161 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Heater Circuit Malfunction (Bank 2 Sensor 2) – Downstream | Faulty rear most oxygen sensor, Faulty wiring/connections, Short or open ground in the wiring |
| P0068 – Meaning, Causes, Symptoms, & Fixes | MAP/MAF – Throttle Position Correlation | Vacuum leak, Dirty air filter, Intake air leak, Clogged or disconnected line to MAP sensor, Carbon buildup on the throttle body, Faulty mass airflow sensor, Dirty mass airflow sensor, Faulty manifold absolute pressure sensor, A faulty throttle position sensor, Poor electrical connections at sensors |
| Top Makes and Models with DTC P0101 | Mass Air Flow (MAF) Circuit/Performance Malfunction | Dirty, obstructed, or faulty mass air flow sensor, Damaged or disconnected air intake boot (snorkel), Vacuum leak, Clogged or improperly installed air filter, Clogged catalytic converter / restricted exhaust |
| P0102 – Meaning, Causes, Symptoms, & Fixes | Mass or Circuit Airflow (MAF) Circuit Low Voltage Input | Dirty air filter, Faulty MAF sensor, Corroded/Damaged MAF circuit terminals, Carbon covered MAF sensor screens |
| P0104 – Meaning, Causes, Symptoms, & Fixes | Mass Air Flow (MAF) Electrical Circuit Erratic and Irregular Output | Dirty or damaged air filter, Leaking vacuum hoses or intake gaskets, Debris covering MAF sensing element, Faulty MAF, Faulty electrical connection to MAF sensor, Corroded/Damaged MAF circuit terminals |
| P0106 – Meaning, Causes, Symptoms, & Fixes | Manifold Air Pressure (MAP) Barometric Pressure Sensor Electric Circuit Output Range and Performance Problem | Faulty MAP sensor, Faulty MAP sensor wiring, Leaks in air intake system, MAP sensor affected by water or dirt |
| P0113 Engine Code Explained: Causes, Symptoms & How To Fix It | Intake Air Temperature (IAT) Sensor Circuit High Input Problem | Faulty or loose IAT sensor, Faulty or loose wiring connections |
| P0122 – Meaning, Causes, Symptoms, & Fixes | Throttle Position Sensor/Switch (TPS) A Circuit Low Input | TPS Mounted Incorrectly, Faulty or Frayed TPS Wiring, TPS Circuit Short to Ground, Faulty TPS |
| P0171 Engine Code | System Too Lean (Bank 1) | Bank 1 has too much air or not enough fuel | Faulty or dirty mass airflow sensor, Vacuum leaks (PCV hoses, vacuum hoses, intake manifold gasket), Weak fuel pump, Clogged or dirty fuel injectors, Clogged fuel filter, Exhaust leak, Faulty oxygen sensor, Faulty air-fuel ratio sensor |
| P0172 – Meaning, Causes, Symptoms, & Fixes | Bank 1 has too much fuel or not enough air | Faulty or dirty mass airflow sensor, Vacuum leaks (PCV hoses, vacuum hoses, intake manifold gasket), Weak fuel pump, Clogged or dirty fuel injectors, Clogged fuel filter, Exhaust leak, Faulty oxygen sensor, Faulty air-fuel ratio sensor |
| P0175 – Meaning, Causes, Symptoms, & Fixes | Bank 2 has too much fuel or not enough air | Faulty or dirty mass airflow sensor, Vacuum leaks (PCV hoses, vacuum hoses, intake manifold gasket), Weak fuel pump, Clogged or dirty fuel injectors, Clogged fuel filter, Exhaust leak, Faulty oxygen sensor, Faulty air-fuel ratio sensor |
| P0174 – Meaning, Causes, Symptoms, & Fixes | Bank 2 has too much air or not enough fuel | Dirty or faulty mass airflow sensor, Vacuum leaks (PCV hoses, vacuum hoses, intake manifold gasket), Weak fuel pump, Clogged or dirty fuel injectors, Clogged fuel filter, Exhaust leak, Faulty oxygen sensor, Faulty air-fuel ratio sensor |
| P0300 Engine Code | Random, Multiple Misfire Detected | Random, Multiple Misfire Detected | Defective Spark Plug, Damaged Spark Plug Wire, Bad Ignition Coil, Faulty Camshaft or Crankshaft Position Sensor, Defective Fuel Pressure Regulator, Vacuum Leak, Bad Fuel Injector, Faulty Oxygen Sensor, Defective Fuel Pump, Leaking Head Gasket, Malfunctioning Catalytic Converter |
| P0301 – Meaning, Causes, Symptoms, & Fixes | Cylinder 1 misfire detected | Faulty or worn spark plugs and/or spark plug wires, Ignition issues including failing or damaged ignition coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft and/or crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel that is old or contaminated |
| P0302 – Meaning, Causes, Symptoms, & Fixes | Cylinder 2 misfire detected | Faulty or worn spark plugs and/or spark plug wires, Ignition issues including failing or damaged ignition coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft and/or crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel that is old or contaminated |
| P0303 – Meaning, Causes, Symptoms, & Fixes | Cylinder 3 misfire detected | Faulty or worn spark plugs, Faulty spark plug wires or coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft sensor defective, Crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel |
| P0304 Engine Code | Cylinder 4 Misfire Detected | Cylinder 4 misfire detected | Defective Spark Plug, Damaged Spark Plug Wire, Bad Ignition Coil, Faulty Camshaft or Crankshaft Position Sensor, Defective Fuel Pressure Regulator, Vacuum Leak, Bad Fuel Injector, Faulty Oxygen Sensor, Defective Fuel Pump, Leaking Head Gasket, Malfunctioning Catalytic Converter |
| P0305 – Meaning, Causes, Symptoms, & Fixes | Cylinder 5 misfire detected | Faulty or worn spark plugs and/or spark plug wires, Ignition issues including failing or damaged ignition coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft and/or crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel that is old or contaminated |
| P0306 – Meaning, Causes, Symptoms, & Fixes | Cylinder 6 misfire detected | Faulty or worn spark plugs and/or spark plug wires, Ignition issues including failing or damaged ignition coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft and/or crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel that is old or contaminated |
| P0307 – Meaning, Causes, Symptoms, & Fixes | Cylinder 7 misfire detected | Faulty or worn spark plugs and/or spark plug wires, Ignition issues including failing or damaged ignition coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft and/or crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel that is old or contaminated |
| P0308 – Meaning, Causes, Symptoms, & Fixes | Cylinder 8 misfire detected | Faulty or worn spark plugs and/or spark plug wires, Ignition issues including failing or damaged ignition coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft and/or crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel that is old or contaminated |
| P0309 – Meaning, Causes, Symptoms, & Fixes | Cylinder 9 misfire detected | Faulty or worn spark plugs and/or spark plug wires, Ignition issues including failing or damaged ignition coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft and/or crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel that is old or contaminated |
| P0310 – Meaning, Causes, Symptoms, & Fixes | Cylinder 10 misfire detected | Faulty or worn spark plugs and/or spark plug wires, Ignition issues including failing or damaged ignition coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft and/or crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel that is old or contaminated |
| P0311 – Meaning, Causes, Symptoms, & Fixes | Cylinder 11 misfire detected | Faulty or worn spark plugs and/or spark plug wires, Ignition issues including failing or damaged ignition coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft and/or crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel that is old or contaminated |
| P0312 – Meaning, Causes, Symptoms, & Fixes | Cylinder 12 misfire detected | Faulty or worn spark plugs and/or spark plug wires, Ignition issues including failing or damaged ignition coils, Distributor failure, Faulty fuel injector, Vacuum leak, Low fuel pressure, Camshaft and/or crankshaft sensor defective, Engine timing off, Leaking head gasket, Low engine compression, Poor quality fuel that is old or contaminated |
| P0316 – Meaning, Causes, Symptoms, & Fixes | Engine Misfire Detected on Startup (First 1000 Revolutions) | Faulty Ignition System Components, Faulty Ignition Coil, Faulty Fuel Injector, Lack of Fresh or Proper Fuel, Faulty Crankshaft or Camshaft Position Sensors, Damaged or Frayed Crankshaft Position Sensor Wires, Engine Vacuum Leaks |
| P0325 – Meaning, Causes, Symptoms, & Fixes | Knock Sensor 1 Circuit Malfunction (Bank 1) | Engine is running excessively lean, Faulty or damaged knock sensor wiring, Faulty sensor 1 Bank 1 knock sensor, Engine coolant system fault |
| P0330 – Meaning, Causes, Symptoms, & Fixes | Knock Sensor 2 Circuit Malfunction (Bank 2) | Engine is running excessively lean, Faulty or damaged knock sensor wiring, Faulty sensor 2 Bank 2 knock sensor, Engine coolant system fault |
| P0332 – Meaning, Causes, Symptoms, & Fixes | Knock Sensor 2 Low Circuit Input (Bank 2) | Faulty knock sensor, Fault in the knock sensor circuitry, Faulty EGR system |
| P0401 – Meaning, Causes, Symptoms, & Fixes | Exhaust Gas Recirculation (EGR) Flow Insufficient Detected | Clogged or restricted EGR passages due to excess carbon, Faulty EGR valve, EGR temperature sensor is covered with carbon |
| P0404 – Meaning, Causes, Symptoms, & Fixes | Exhaust Gas Recirculation Circuit Range/Performance | Faulty EGR valve, Faulty EGR sensor, EGR sensor wiring/connector problems, EGR valve movement isn't smooth, Carbon buildup in EGR valve |
| P0406 – Meaning, Causes, Symptoms, & Fixes | Exhaust Gas Recirculation Sensor "A" Circuit High | Faulty EGR valve sensor, Open/Shorted EGR sensor circuit, Dirty EGR valve, Disconnected wiring in EGR circuit |
| P0410 – Meaning, Causes, Symptoms, & Fixes | Secondary Air Injection System Malfunction | Malfunctioning air pump/air pump relay, Faulty air pump check valves, Blocked air injection system, Blown air injection fuse |
| P0420 Engine Code | Catalyst System Efficiency Below Threshold (Bank 1) | Catalyst system efficiency below threshold (Bank 1) | Catalytic Converter Failure, Misfires or an incorrect air-fuel ratio,Worn or internally failing catalytic converter, Faulty oxygen sensor, Faulty air-fuel sensor, A leak in the exhaust system, Misfire, Rich or Lean air-fuel ratio, Leaded Gasoline |
| P0421 – Meaning, Causes, Symptoms, & Fixes | Bank 1 Catalytic Converter Efficiency is Below Threshold on Cold Start | O2 Sensor, A/F Sensor, Bank 1 Catalytic Converter, Spark Plugs, Ignition Coil(s) |
| P0430 – Meaning, Causes, Symptoms, & Fixes | Catalyst system efficiency below threshold (Bank 2) | Faulty oxygen sensor, Faulty air-fuel sensor, Worn or internally failing catalytic converter, A leak in the exhaust system, Misfire, Rich or Lean air-fuel ratio, Leaded Gasoline |
| P0440 – Meaning, Causes, Symptoms, & Fixes | Evaporative Emission Control System Malfunction | Missing, defective, damaged, or loose gas cap, Leaking or disconnected EVAP hose, Faulty purge volume valve, Faulty canister vent control valve, Charcoal canister leak, Leaking fuel tank |
| P0441 – Meaning, Causes, Symptoms, & Fixes | Evaporative Emission Control System Incorrect Purge Flow | Faulty purge valve (solenoid), Damaged or cracked charcoal canister, Loose damaged or missing gas cap, Damaged or loose EVAP hoses |
| P0442 – Meaning, Causes, Symptoms, & Fixes | Evaporative emission control system leak (medium) | Loose or damaged gas cap, Leaking or disconnected EVAP hose, Faulty purge volume control valve, Faulty canister vent control valve, Charcoal canister leak, Leaking fuel tank |
| P0443 – Meaning, Causes, Symptoms, & Fixes | Evaporative Emission Control System Purge Control Valve Circuit Malfunction | Short in control circuit wiring, Short in purge valve wiring, Faulty vent valve solenoid, Faulty purge valve solenoid, Faulty ECM |
| P0446 – Meaning, Causes, Symptoms, & Fixes | Evaporative Emission Control System Vent Control Circuit Malfunction | Missing, defective, damaged, or loose gas cap (most common), Defective EVAP Canister Vent Control Valve, Distorted, damaged or cracked Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective or damaged fuel tank, Open or shorted electrical connections |
| P0449 – Meaning, Causes, Symptoms, & Fixes | Evaporative System (EVAP) Vent Circuit Control Malfunction | Missing, defective, damaged, or loose gas cap (most common), Defective EVAP Canister Vent Control Valve, Distorted, damaged or cracked Fuel Tank Filler Neck, Torn or punctured Evaporative system hose(s), Defective Fuel Tank Sending Unit gasket or seal, Split or damaged Carbon Canister, Defective or damaged fuel tank, Open or shorted electrical connections |
| P0452 – Meaning, Causes, Symptoms, & Fixes | Evaporative Emission Control System Pressure Sensor Low Input | Faulty Evap Pressure Sensor, Faulty Fuel Tank Pressure Sensor, Loose/leaking gas cap, Cracked evaporative line, Leaking evaporative seals, Open/shorted wiring, Poor connection at sensor |
| P0455 Engine Code Explained: Causes, Symptoms & How To Fix It | System Gross Leak Evaporative System Malfunction | Missing, defective, damaged, or loose gas cap (*most Common), Faulty or stuck EVAP vent control valve, Faulty or stuck EVAP purge volume control valve, Cracked or disconnected EVAP hose, Cracked or damaged charcoal canister |
| P0456 Engine Code | Evaporative Emission Control System—Small Leak Detected | Evaporative Emission Control System—Small Leak Detected | Faulty gas cap, Defective charcoal canister, Bad purge or vent valve, Damaged EVAP line |
| P0457 – Meaning, Causes, Symptoms, & Fixes | Evaporative Emission (EVAP) Control System Leak Detected | Loose or damaged gas cap, Leaking or disconnected EVAP hose, Faulty purge volume control valve, Faulty canister vent control valve, Charcoal canister leak, Leaking fuel tank |
| P0496 – Meaning, Causes, Symptoms, & Fixes | EVAP Flow During a Non-Purge Condition | Faulty EVAP Purge Volume Control Valve (most common), Faulty EVAP pressure sensor, Leaking EVAP system hose, Poor electrical connections, Leaking Charcoal Canister |
| P0507 Engine Code | Idle Speed Too High | Idle Control System RPM Higher Than Expected | Vacuum leak, Dirty or defective throttle body, Faulty mass air flow (MAF) sensor, Bad idle air control valve, Defective power steering pressure switch |
| P2098 – Meaning, Causes, Symptoms, & Fixes | Bank 2 Post Catalyst Fuel Trim Too Lean | Dirty or faulty mass airflow sensor, Vacuum leaks (PCV hoses, vacuum hoses, intake manifold gasket), Weak fuel pump, Clogged or dirty fuel injectors, Clogged fuel filter, Exhaust leak, Faulty oxygen sensor, Faulty air-fuel ratio sensor |
| P2187 – Meaning, Causes, Symptoms, & Fixes | Bank 1 System Too Lean at Idle | Dirty or faulty mass airflow sensor, Vacuum leaks (PCV hoses, vacuum hoses, intake manifold gasket), Oil cap not installed, Weak fuel pump, Clogged or dirty fuel injectors, Clogged fuel filter, Exhaust leak, Faulty oxygen sensor, Faulty air-fuel ratio sensor |
| P2195 – Meaning, Causes, Symptoms, & FixesP2196 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Signal Stuck Lean- Bank 1 Sensor 1 | Frayed oxygen sensor circuit wiring/connectors, Faulty bank 1 heated oxygen sensor 1, Malfunctioning fuel injector, Vacuum leaks, Fuel pressure too low, Debris in Mass Airflow Sensor, Exhaust leak |
| P2196 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Signal Stuck Rich (Bank 1, Sensor 1) | Frayed or broken oxygen sensor circuit wiring/connectors, Faulty oxygen sensor 1 bank 1, Dirty Mass Air Flow (MAF), Vacuum leaks, Exhaust leaks, Fuel pressure too high, Leaking fuel injector, Malfunctioning ECM |
| P2197 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Signal Stuck Lean- Bank 2 Sensor 1 | Frayed oxygen sensor circuit wiring/connectors, Faulty bank 2 heated oxygen sensor 1, Malfunctioning fuel injector, Vacuum leaks, Fuel pressure too low, Debris in Mass Airflow Sensor, Exhaust leak |
| P2198 – Meaning, Causes, Symptoms, & Fixes | O2 Sensor Signal Stuck Rich (Bank 2, Sensor 1) | Frayed or broken oxygen sensor circuit wiring/connectors, Faulty oxygen sensor 1 bank 2, Dirty Mass Air Flow (MAF), Vacuum leaks, Exhaust leaks, Fuel pressure too high, Leaking fuel injector, Malfunctioning ECM |
| DTC Code | Standard Error Message | Possible Causes |
|---|---|---|
| P0117 – Meaning, Causes, Symptoms, & Fixes | Engine Coolant Temperature (ECT) Sensor Circuit has lower than normal voltage | Rusted/Dirty Engine Coolant, Air Pocket in Coolant System, Frayed ECT wiring, Malfunctioning ECT Sensor, Open ECT circuit, Faulty ECM |
| P0118 – Meaning, Causes, Symptoms, & Fixes | H02S2 Heater Control Circuit Low (Bank 2, Sensor 2) | Rusted/Dirty Engine Coolant, Air Pocket in Coolant System, Frayed ECT wiring, Malfunctioning ECT Sensor, Open ECT circuit, Faulty ECM |
| P0125 – Meaning, Causes, Symptoms, & Fixes | Insufficient coolant temperature for closed-loop fuel control | Low engine coolant, Stuck open thermostat, Missing thermostat, Faulty coolant temperature sensor |
| P0128 Engine Code | Coolant Temperature Below Thermostat Regulating Temperature | Coolant Thermostat Temperature Below Regulating Temperature | Faulty/stuck open thermostat (most common), Missing Thermostat, Faulty coolant temperature sensor, Faulty wiring for coolant temperature circuit |
| P0521 – Meaning, Causes, Symptoms, & Fixes | Engine Oil Pressure Sensor/Switch Range/Performance | Faulty oil pressure sensor (sometimes called an oil pressure sending unit), Faulty wiring/connections, Short or open ground in the wiring, Blown Fuse, Engine coolant temperature sensor is not operating correctly, Faulty Power Control Module |
| DTC Code | Standard Error Message | Possible Causes |
|---|---|---|
| P0463 – Meaning, Causes, Symptoms, & Fixes | Fuel Level Sensor Circuit High Input | Faulty fuel level sensor, Faulty fuel pump, Malfunctioning fuel level sensor float, Faulty gauge cluster, Damaged fuel tank, Frayed wiring/connection to fuel sensor harness |
| DTC Code | Standard Error Message | Possible Causes |
|---|---|---|
| P0562 – Meaning, Causes, Symptoms, & Fixes | System voltage low | Faulty wiring, including ground connections, A defective alternator, A defective voltage regulator, A defective battery and/or battery cables, A large battery drain, A faulty PCM (rare) |
| DTC Code | Standard Error Message | Possible Causes |
|---|---|---|
| P0335 – Meaning, Causes, Symptoms, & Fixes | Crankshaft Position Sensor "A" Circuit Malfunction (Bank 1) | Damaged or defective crankshaft position sensor, Broken timing belt or chain, Rough running/misfiring engine, Failed ECM |
| P0340 Engine Code Explained: Causes, Symptoms & How To Fix It | Camshaft Position Sensor Circuit Malfunction | A defective camshaft position sensor, Damaged or dirty reluctor ring on the camshaft, Defective, corroded, shorted camshaft position sensor circuit wiring, Defective, corroded, shorted camshaft position sensor circuit connector, A faulty crankshaft position sensor, Stretched or misaligned timing components, ECM software update needed, Faulty ECM |
| P0345 – Meaning, Causes, Symptoms, & Fixes | Camshaft Position Sensor Circuit Malfunction | A defective camshaft position sensor, Damaged or dirty reluctor ring on the camshaft, Defective, corroded, shorted camshaft position sensor circuit wiring, Defective, corroded, shorted camshaft position sensor circuit connector, A faulty crankshaft position sensor, Stretched or misaligned timing components, ECM software update needed, Faulty ECM |
| P0606 – Meaning, Causes, Symptoms, & Fixes | The processor in the Engine Control Module (ECM) or Power Control Module (PCM) has a fault. | Faulty ECM/PCM, Faulty power to ECM/PCM, Faulty ground to ECM/PCM |
| P0700 – Meaning, Causes, Symptoms, & Fixes | Transmission Control System Malfunction | Defective shift solenoids, Defective Valve Body, Faulty Transmission, Shorted or open circuit Transmission Control Module (TCM), Faulty Transmission Control Module (TCM) |
| P0705 – Meaning, Causes, Symptoms, & Fixes | Transmission Range Sensor Circuit Malfunction (PRNDL Input) | Faulty Transmission Range Sensor/Switch (TRS), Faulty Valve Body (TRS can be part of this), Faulty Transmission (TRS can be part of this), Misadjusted TRS, Frayed or damaged wiring to the TRS, Humidity in Tail Lights |
| P0715 – Meaning, Causes, Symptoms, & Fixes | Malfunction in the transmission input/turbine speed sensor circuit | Failed input/turbine speed sensor, Failed output speed sensor, Failed torque converter, Faulty wiring, Debris on input/turbine speed sensor, Debris on output speed sensor, Damaged reluctor ring for input/turbine speed sensor |
| P2135 – Meaning, Causes, Symptoms, & Fixes | The voltage readings going to the Engine Control Module (ECM) from the throttle body position sensor and accelerator pedal position sensor do not match each other. | Throttle position sensor, Throttle body actuator, Accelerator pedal position sensor, Damaged wiring, Poor electrical connections |
| P2135 – Meaning, Causes, Symptoms, & Fixes | The voltage readings going to the Engine Control Module (ECM) from the throttle body position sensor and accelerator pedal position sensor do not match each other. | Throttle position sensor, Throttle body actuator, Accelerator pedal position sensor, Damaged wiring, Poor electrical connections |
| P2138 – Meaning, Causes, Symptoms, & Fixes | The voltage readings going to the Engine Control Module (ECM) from the throttle body position sensor and accelerator pedal position sensor do not match each other. | Throttle position sensor, Throttle body actuator, Accelerator pedal position sensor, Damaged wiring, Poor electrical connections |
Decode OBD2 Codes Quickly
Welcome to our OBD2 code resource hub, designed to help you troubleshoot car issues with ease. We break down over 100 diagnostic trouble codes (DTCs) and what they mean. Our detailed explanations cover causes, symptoms, and fixes for each code, giving you the confidence to make informed repair decisions. We’ve also written an article on the most common OBD2 codes like P0420, P0301, and P0171 if you just want a quick reference.
Below, you’ll find all of our OBD2 code articles in numerical order and below it, the same codes organized by the car system they are related to. This should make it easy to find what you are looking for.
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