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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

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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 985–1008 of 1223

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U0691Lost Communication With Exhaust Pressure Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0691 concerns lost communication with exhaust pressure sensor a. Learn what this fault indicates and where to begin diagnosis.U0692Lost Communication With Exhaust Pressure Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0692 concerns lost communication with exhaust pressure sensor b. Learn what this fault indicates and where to begin diagnosis.U0693Lost Communication With Humidity SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0693 concerns lost communication with humidity sensor. Learn what this fault indicates and where to begin diagnosis.U0694Lost Communication With Hybrid/EV Battery Pack Coolant Pump ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0694 concerns lost communication with hybrid/ev battery pack coolant pump a. Learn what this fault indicates and where to begin diagnosis.U0695Lost Communication With Hybrid/EV Battery Pack Coolant Pump BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0695 concerns lost communication with hybrid/ev battery pack coolant pump b. Learn what this fault indicates and where to begin diagnosis.U0696Lost Communication With Particulate Filter Pressure Sensor CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0696 concerns lost communication with particulate filter pressure sensor c. Learn what this fault indicates and where to begin diagnosis.U0697Lost Communication With Particulate Filter Pressure Sensor DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0697 concerns lost communication with particulate filter pressure sensor d. Learn what this fault indicates and where to begin diagnosis.U0698Lost Communication with Coolant Pump “E”Check soonNetwork & Communication45–120 minutes for initial diagnosisU0698 concerns lost communication with coolant pump “e”. Learn what this fault indicates and where to begin diagnosis.U0699Lost Communication with Coolant Pump “F”Check soonNetwork & Communication45–120 minutes for initial diagnosisU0699 concerns lost communication with coolant pump “f”. Learn what this fault indicates and where to begin diagnosis.U069ALost Communication With Exhaust Gas Temperature Sensor Bank 1 Sensor 3Check soonNetwork & Communication45–120 minutes for initial diagnosisU069A concerns lost communication with exhaust gas temperature sensor bank 1 sensor 3. Learn what this fault indicates and where to begin diagnosis.U069BLost Communication With Exhaust Gas Temperature Sensor Bank 1 Sensor 4Check soonNetwork & Communication45–120 minutes for initial diagnosisU069B concerns lost communication with exhaust gas temperature sensor bank 1 sensor 4. Learn what this fault indicates and where to begin diagnosis.U069CLost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 3Check soonNetwork & Communication45–120 minutes for initial diagnosisU069C concerns lost communication with exhaust gas temperature sensor bank 2 sensor 3. Learn what this fault indicates and where to begin diagnosis.U069DLost Communication With Exhaust Gas Temperature Sensor Bank 2 Sensor 4Check soonNetwork & Communication45–120 minutes for initial diagnosisU069D concerns lost communication with exhaust gas temperature sensor bank 2 sensor 4. Learn what this fault indicates and where to begin diagnosis.U069ELost Communication with Coolant Heater ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU069E concerns lost communication with coolant heater a. Learn what this fault indicates and where to begin diagnosis.U069FLost Communication With Exhaust Pressure Sensor CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU069F concerns lost communication with exhaust pressure sensor c. Learn what this fault indicates and where to begin diagnosis.U0901Invalid Data from Ion Sense ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0901 concerns invalid data from ion sense module. Learn what this fault indicates and where to begin diagnosis.U3000Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3000 concerns control module. Learn what this fault indicates and where to begin diagnosis.U3001Control Module Improper Shutdown PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3001 concerns control module improper shutdown performance. Learn what this fault indicates and where to begin diagnosis.U3002Vehicle Identification NumberCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3002 concerns vehicle identification number. Learn what this fault indicates and where to begin diagnosis.U3003Battery VoltageCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3003 concerns battery voltage. Learn what this fault indicates and where to begin diagnosis.U3004Accessory Power RelayCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3004 concerns accessory power relay. Learn what this fault indicates and where to begin diagnosis.U3005Retained Accessory PowerCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3005 concerns retained accessory power. Learn what this fault indicates and where to begin diagnosis.U3006Control Module Input Power A Circuit/OpenCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3006 concerns control module input power a circuit/open. Learn what this fault indicates and where to begin diagnosis.U3007Control Module Input Power B Circuit/OpenCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3007 concerns control module input power b circuit/open. Learn what this fault indicates and where to begin diagnosis.