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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 7777–7800 of 8256

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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.U062DLost Communication With A/C Refrigerant Distribution Valve Actuator “D”Check soonNetwork & Communication45–120 minutes for initial diagnosisU062D concerns lost communication with a/c refrigerant distribution valve actuator “d”. Learn what this fault indicates and where to begin diagnosis.U062ELost Communication With A/C Refrigerant Expansion Valve ActuatorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU062E concerns lost communication with a/c refrigerant expansion valve actuator. Learn what this fault indicates and where to begin diagnosis.U062FLost Communication With Coolant Pump CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU062F concerns lost communication with coolant pump c. Learn what this fault indicates and where to begin diagnosis.U0630Lost Communication With Engine Coolant Temperature Sensor 4Check soonNetwork & Communication45–120 minutes for initial diagnosisU0630 concerns lost communication with engine coolant temperature sensor 4. Learn what this fault indicates and where to begin diagnosis.U0631Lost Communication With Engine Coolant Temperature Sensor 5Check soonNetwork & Communication45–120 minutes for initial diagnosisU0631 concerns lost communication with engine coolant temperature sensor 5. Learn what this fault indicates and where to begin diagnosis.U0632Lost Communication With Fan 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU0632 concerns lost communication with fan 1. Learn what this fault indicates and where to begin diagnosis.U0633Lost Communication With Fan 2Check soonNetwork & Communication45–120 minutes for initial diagnosisU0633 concerns lost communication with fan 2. Learn what this fault indicates and where to begin diagnosis.U0634Lost Communication With Hybrid/EV Battery Pack Coolant Temperature Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0634 concerns lost communication with hybrid/ev battery pack coolant temperature sensor a. Learn what this fault indicates and where to begin diagnosis.U0635Lost Communication With Hybrid/EV Battery Pack Coolant Temperature Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0635 concerns lost communication with hybrid/ev battery pack coolant temperature sensor b. Learn what this fault indicates and where to begin diagnosis.U0636Lost Communication With Hybrid/EV Battery Pack Coolant Control Valve ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0636 concerns lost communication with hybrid/ev battery pack coolant control valve a. Learn what this fault indicates and where to begin diagnosis.U0637Lost Communication With Hybrid/EV Battery Pack Coolant Control Valve BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0637 concerns lost communication with hybrid/ev battery pack coolant control valve b. Learn what this fault indicates and where to begin diagnosis.U0638Lost Communication With Hybrid/EV Electronics Coolant Temperature Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0638 concerns lost communication with hybrid/ev electronics coolant temperature sensor a. Learn what this fault indicates and where to begin diagnosis.