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Find codes by symptomChoose what you notice to search matching code guides.

Rough idle or shakingVibration while stopped Hard to startLong cranking or no-start Engine stallsCuts out at idle or on the road Hesitates or loses powerSlow response when accelerating Battery light is onCharging system warning Harsh gear changesDelayed or rough shifting

A symptom can have several causes. Treat matching codes as clues and follow the diagnostic checks in each guide.

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Engine1049 Emissions515 Fuel1016 Sensors & Electronics2110 Transmission866 Electrical & Charging1797 Body & Restraints193 Chassis & Brakes479 Network & Communication1228

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Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

All families9253 P · Powertrain7353 B · Body193 C · Chassis479 U · Network1228

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These are generic OBD2 definitions. Exact make, model, engine, and year compatibility will appear after vehicle-fitment data is added.

Diagnostic codes

Showing 7849–7872 of 8256

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U0669Lost Communication With EGR Sensor DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0669 concerns lost communication with egr sensor d. Learn what this fault indicates and where to begin diagnosis.U066ALost Communication With EGR Sensor ECheck soonNetwork & Communication45–120 minutes for initial diagnosisU066A concerns lost communication with egr sensor e. Learn what this fault indicates and where to begin diagnosis.U066BLost Communication With Turbocharger/Supercharger Bypass Valve B Position SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU066B concerns lost communication with turbocharger/supercharger bypass valve b position sensor. Learn what this fault indicates and where to begin diagnosis.U066CLost Communication With Exhaust Heat Exchanger Bypass Valve Actuator BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU066C concerns lost communication with exhaust heat exchanger bypass valve actuator b. Learn what this fault indicates and where to begin diagnosis.U066DLost Communication With Charge Air Cooler Temperature Sensor Bank 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU066D concerns lost communication with charge air cooler temperature sensor bank 1. Learn what this fault indicates and where to begin diagnosis.U066ELost Communication With Charge Air Cooler Temperature Sensor Bank 2Check soonNetwork & Communication45–120 minutes for initial diagnosisU066E concerns lost communication with charge air cooler temperature sensor bank 2. Learn what this fault indicates and where to begin diagnosis.U066FLost Communication With Low Pressure Fuel System SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU066F concerns lost communication with low pressure fuel system sensor. Learn what this fault indicates and where to begin diagnosis.U0670Lost Communication With Fuel Temperature Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0670 concerns lost communication with fuel temperature sensor a. Learn what this fault indicates and where to begin diagnosis.U0671Lost Communication With Fuel Temperature Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0671 concerns lost communication with fuel temperature sensor b. Learn what this fault indicates and where to begin diagnosis.U0672Lost Communication With Engine Coolant PumpCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0672 concerns lost communication with engine coolant pump. Learn what this fault indicates and where to begin diagnosis.U0673Lost Communication With Ion Sense ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0673 concerns lost communication with ion sense module. Learn what this fault indicates and where to begin diagnosis.U0674Lost Communication With Wastegate Position Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0674 concerns lost communication with wastegate position sensor b. Learn what this fault indicates and where to begin diagnosis.U0675Lost Communication With Turbocharger/Supercharger Speed Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0675 concerns lost communication with turbocharger/supercharger speed sensor a. Learn what this fault indicates and where to begin diagnosis.U0676Lost Communication With Fuel Level Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0676 concerns lost communication with fuel level sensor a. Learn what this fault indicates and where to begin diagnosis.U0677Lost Communication With Fuel Level Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0677 concerns lost communication with fuel level sensor b. Learn what this fault indicates and where to begin diagnosis.U0678Lost Communication With Fuel Level Sensor CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0678 concerns lost communication with fuel level sensor c. Learn what this fault indicates and where to begin diagnosis.U0679Lost Communication With Transmission Fluid Pressure Sensor/Switch ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0679 concerns lost communication with transmission fluid pressure sensor/switch a. Learn what this fault indicates and where to begin diagnosis.U067ALost Communication With Transmission Fluid Pressure Sensor/Switch BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU067A concerns lost communication with transmission fluid pressure sensor/switch b. Learn what this fault indicates and where to begin diagnosis.U067BLost Communication With Engine Disconnect Clutch Pressure SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU067B concerns lost communication with engine disconnect clutch pressure sensor. Learn what this fault indicates and where to begin diagnosis.U067CLost Communication With Fan 3Check soonNetwork & Communication45–120 minutes for initial diagnosisU067C concerns lost communication with fan 3. Learn what this fault indicates and where to begin diagnosis.U067DLost Communication With Fan 4Check soonNetwork & Communication45–120 minutes for initial diagnosisU067D concerns lost communication with fan 4. Learn what this fault indicates and where to begin diagnosis.U067ELost Communication With Exhaust Pressure Control Valve B Sensor/SwitchCheck soonNetwork & Communication45–120 minutes for initial diagnosisU067E concerns lost communication with exhaust pressure control valve b sensor/switch. Learn what this fault indicates and where to begin diagnosis.U067FLost Communication With Barometric Pressure Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU067F concerns lost communication with barometric pressure sensor a. Learn what this fault indicates and where to begin diagnosis.U0680Lost Communication With Barometric Pressure Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0680 concerns lost communication with barometric pressure sensor b. Learn what this fault indicates and where to begin diagnosis.