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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 7801–7824 of 8256

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U0639Lost Communication With Hybrid/EV Electronics Coolant Temperature Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0639 concerns lost communication with hybrid/ev electronics coolant temperature sensor b. Learn what this fault indicates and where to begin diagnosis.U063ALost Communication With Hybrid/EV Electronics Coolant Temperature Sensor CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU063A concerns lost communication with hybrid/ev electronics coolant temperature sensor c. Learn what this fault indicates and where to begin diagnosis.U063BLost Communication With Coolant Bypass Valve Actuator ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU063B concerns lost communication with coolant bypass valve actuator a. Learn what this fault indicates and where to begin diagnosis.U063CLost Communication With Coolant Bypass Valve Actuator BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU063C concerns lost communication with coolant bypass valve actuator b. Learn what this fault indicates and where to begin diagnosis.U063DLost Communication With Hybrid/EV Electronics Coolant Pump ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU063D concerns lost communication with hybrid/ev electronics coolant pump a. Learn what this fault indicates and where to begin diagnosis.U063ELost Communication With Exhaust Heat Exchanger Bypass Valve Actuator ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU063E concerns lost communication with exhaust heat exchanger bypass valve actuator a. Learn what this fault indicates and where to begin diagnosis.U063FLost Communication With Engine Coolant Flow Control Valve Position SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU063F concerns lost communication with engine coolant flow control valve position sensor. Learn what this fault indicates and where to begin diagnosis.U0640Lost Communication With EVAP Fuel Vapor Temperature Sensor CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0640 concerns lost communication with evap fuel vapor temperature sensor circuit. Learn what this fault indicates and where to begin diagnosis.U0641Lost Communication With EVAP System Pressure Sensor/Switch Circuit ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0641 concerns lost communication with evap system pressure sensor/switch circuit a. Learn what this fault indicates and where to begin diagnosis.U0642Lost Communication With EVAP System Pressure Sensor/Switch Circuit BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0642 concerns lost communication with evap system pressure sensor/switch circuit b. Learn what this fault indicates and where to begin diagnosis.U0643Lost Communication With Turbocharger/Supercharger A Temperature SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0643 concerns lost communication with turbocharger/supercharger a temperature sensor. Learn what this fault indicates and where to begin diagnosis.U0644Lost Communication With Wastegate Position Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0644 concerns lost communication with wastegate position sensor a. Learn what this fault indicates and where to begin diagnosis.U0645Lost Communication With Active Air Dam ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0645 concerns lost communication with active air dam module. Learn what this fault indicates and where to begin diagnosis.U0646Lost Communication With Motor Electronics Coolant Pump ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0646 concerns lost communication with motor electronics coolant pump a. Learn what this fault indicates and where to begin diagnosis.U0647Lost Communication With Motor Electronics Coolant Pump BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0647 concerns lost communication with motor electronics coolant pump b. Learn what this fault indicates and where to begin diagnosis.U0648Lost Communication With Motor Electronics Coolant Pump CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0648 concerns lost communication with motor electronics coolant pump c. Learn what this fault indicates and where to begin diagnosis.U0649Lost Communication With Coolant Pump DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0649 concerns lost communication with coolant pump d. Learn what this fault indicates and where to begin diagnosis.U064ALost Communication With Hybrid/EV Battery Pack Current Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU064A concerns lost communication with hybrid/ev battery pack current sensor a. Learn what this fault indicates and where to begin diagnosis.U064BLost Communication With Hybrid/EV Battery Pack Current Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU064B concerns lost communication with hybrid/ev battery pack current sensor b. Learn what this fault indicates and where to begin diagnosis.U064CLost Communication With Hybrid/EV Battery Pack Current Sensor CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU064C concerns lost communication with hybrid/ev battery pack current sensor c. Learn what this fault indicates and where to begin diagnosis.U064DLost Communication With Trailer Brake Control SwitchCheck soonNetwork & Communication45–120 minutes for initial diagnosisU064D concerns lost communication with trailer brake control switch. Learn what this fault indicates and where to begin diagnosis.U064ELost Communication With EGR Cooler Bypass Position Sensor Bank 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU064E concerns lost communication with egr cooler bypass position sensor bank 1. Learn what this fault indicates and where to begin diagnosis.U064FLost Communication With Intake Manifold Runner Position Sensor Bank 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU064F concerns lost communication with intake manifold runner position sensor bank 1. Learn what this fault indicates and where to begin diagnosis.U0650Lost Communication With Exhaust Pressure Control Valve A Sensor/SwitchCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0650 concerns lost communication with exhaust pressure control valve a sensor/switch. Learn what this fault indicates and where to begin diagnosis.