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9,253 diagnostic guides

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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

FiltersSeverity · family

Severity

All severities9253 Low priority305 Check soon8256 Urgent621

Code family

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

Vehicle coverage

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

Diagnostic codes

Showing 865–888 of 1228

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U0615Lost Communication With Engine Coolant Bypass Valve ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0615 concerns lost communication with engine coolant bypass valve a. Learn what this fault indicates and where to begin diagnosis.U0616Lost Communication With Engine Coolant Bypass Valve BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0616 concerns lost communication with engine coolant bypass valve b. Learn what this fault indicates and where to begin diagnosis.U0617Lost Communication With Engine Coolant Bypass Valve CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0617 concerns lost communication with engine coolant bypass valve c. Learn what this fault indicates and where to begin diagnosis.U0618Lost Communication With Engine Coolant Bypass Valve DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0618 concerns lost communication with engine coolant bypass valve d. Learn what this fault indicates and where to begin diagnosis.U0619Lost Communication With Reductant Level Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0619 concerns lost communication with reductant level sensor a. Learn what this fault indicates and where to begin diagnosis.U061ALost Communication With Reductant Level Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU061A concerns lost communication with reductant level sensor b. Learn what this fault indicates and where to begin diagnosis.U061BLost Communication With Reductant Level Sensor CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU061B concerns lost communication with reductant level sensor c. Learn what this fault indicates and where to begin diagnosis.U061CLost Communication With Reductant Temperature Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU061C concerns lost communication with reductant temperature sensor a. Learn what this fault indicates and where to begin diagnosis.U061DLost Communication With Reductant Temperature Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU061D concerns lost communication with reductant temperature sensor b. Learn what this fault indicates and where to begin diagnosis.U061ELost Communication with Battery Isolation/Voltage Stabilization Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU061E concerns lost communication with battery isolation/voltage stabilization control module. Learn what this fault indicates and where to begin diagnosis.U061FLost Communication With Exhaust Gas Temperature Sensor Bank 1 Sensor 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU061F concerns lost communication with exhaust gas temperature sensor bank 1 sensor 1. Learn what this fault indicates and where to begin diagnosis.U0620Lost Communication With Exhaust Gas Temperature Sensor Bank 1 Sensor 2Check soonNetwork & Communication45–120 minutes for initial diagnosisU0620 concerns lost communication with exhaust gas temperature sensor bank 1 sensor 2. Learn what this fault indicates and where to begin diagnosis.U0621Lost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU0621 concerns lost communication with exhaust gas temperature sensor bank 2 sensor 1. Learn what this fault indicates and where to begin diagnosis.U0622Lost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 2Check soonNetwork & Communication45–120 minutes for initial diagnosisU0622 concerns lost communication with exhaust gas temperature sensor bank 2 sensor 2. Learn what this fault indicates and where to begin diagnosis.U0623Lost Communication With Coolant Pump “A”Check soonNetwork & Communication45–120 minutes for initial diagnosisU0623 concerns lost communication with coolant pump “a”. Learn what this fault indicates and where to begin diagnosis.U0624Lost Communication With Coolant Pump “B”Check soonNetwork & Communication45–120 minutes for initial diagnosisU0624 concerns lost communication with coolant pump “b”. Learn what this fault indicates and where to begin diagnosis.U0625Lost Communication With Fuel Rail Pressure Sensor Bank 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU0625 concerns lost communication with fuel rail pressure sensor bank 1. Learn what this fault indicates and where to begin diagnosis.U0626Lost Communication With A/C Refrigerant Pressure Sensor “A”Check soonNetwork & Communication45–120 minutes for initial diagnosisU0626 concerns lost communication with a/c refrigerant pressure sensor “a”. Learn what this fault indicates and where to begin diagnosis.U0627Lost Communication With A/C Refrigerant Temperature Sensor “A”Check soonNetwork & Communication45–120 minutes for initial diagnosisU0627 concerns lost communication with a/c refrigerant temperature sensor “a”. Learn what this fault indicates and where to begin diagnosis.U0628Lost Communication With A/C Refrigerant Pressure Sensor “B”Check soonNetwork & Communication45–120 minutes for initial diagnosisU0628 concerns lost communication with a/c refrigerant pressure sensor “b”. Learn what this fault indicates and where to begin diagnosis.U0629Lost Communication With A/C Refrigerant Temperature Sensor “B”Check soonNetwork & Communication45–120 minutes for initial diagnosisU0629 concerns lost communication with a/c refrigerant temperature sensor “b”. Learn what this fault indicates and where to begin diagnosis.U062ALost Communication With A/C Refrigerant Distribution Valve Actuator “A”Check soonNetwork & Communication45–120 minutes for initial diagnosisU062A concerns lost communication with a/c refrigerant distribution valve actuator “a”. Learn what this fault indicates and where to begin diagnosis.U062BLost Communication With A/C Refrigerant Distribution Valve Actuator “B”Check soonNetwork & Communication45–120 minutes for initial diagnosisU062B concerns lost communication with a/c refrigerant distribution valve actuator “b”. Learn what this fault indicates and where to begin diagnosis.U062CLost Communication With A/C Refrigerant Distribution Valve Actuator “C”Check soonNetwork & Communication45–120 minutes for initial diagnosisU062C concerns lost communication with a/c refrigerant distribution valve actuator “c”. Learn what this fault indicates and where to begin diagnosis.