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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

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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 7897–7920 of 8256

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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.U3008Control Module Ground ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU3008 concerns control module ground a. Learn what this fault indicates and where to begin diagnosis.U3009Control Module Ground BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3009 concerns control module ground b. Learn what this fault indicates and where to begin diagnosis.U300AIgnition SwitchCheck soonNetwork & Communication45–120 minutes for initial diagnosisU300A concerns ignition switch. Learn what this fault indicates and where to begin diagnosis.U300BIgnition Input Accessory/On/StartCheck soonNetwork & Communication45–120 minutes for initial diagnosisU300B concerns ignition input accessory/on/start. Learn what this fault indicates and where to begin diagnosis.U300CIgnition Input Off/On/StartCheck soonNetwork & Communication45–120 minutes for initial diagnosisU300C concerns ignition input off/on/start. Learn what this fault indicates and where to begin diagnosis.U300DIgnition Input On/StartCheck soonNetwork & Communication45–120 minutes for initial diagnosisU300D concerns ignition input on/start. Learn what this fault indicates and where to begin diagnosis.U300EIgnition Input OnCheck soonNetwork & Communication45–120 minutes for initial diagnosisU300E concerns ignition input on. Learn what this fault indicates and where to begin diagnosis.U300FIgnition Input AccessoryCheck soonNetwork & Communication45–120 minutes for initial diagnosisU300F concerns ignition input accessory. Learn what this fault indicates and where to begin diagnosis.