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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 7921–7944 of 8256

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U3010Ignition Input StartCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3010 concerns ignition input start. Learn what this fault indicates and where to begin diagnosis.U3011Ignition Input OffCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3011 concerns ignition input off. Learn what this fault indicates and where to begin diagnosis.U3012Control Module Improper Wake-up PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3012 concerns control module improper wake-up performance. Learn what this fault indicates and where to begin diagnosis.U3013Control Module Input Power C Circuit/OpenCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3013 concerns control module input power c circuit/open. Learn what this fault indicates and where to begin diagnosis.U3014Control Module Input Power D Circuit/OpenCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3014 concerns control module input power d circuit/open. Learn what this fault indicates and where to begin diagnosis.U3015Control Module Ground CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3015 concerns control module ground c. Learn what this fault indicates and where to begin diagnosis.U3016Control Module Ground DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3016 concerns control module ground d. Learn what this fault indicates and where to begin diagnosis.U3017Control Module Timer/Clock PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3017 concerns control module timer/clock performance. Learn what this fault indicates and where to begin diagnosis.U3018Control Module Input Power Circuit A/B CorrelationCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3018 concerns control module input power circuit a/b correlation. Learn what this fault indicates and where to begin diagnosis.U3019Control Module Input Power Circuit B/C CorrelationCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3019 concerns control module input power circuit b/c correlation. Learn what this fault indicates and where to begin diagnosis.U301AControl Module Wake-up Circuit A/OpenCheck soonNetwork & Communication45–120 minutes for initial diagnosisU301A concerns control module wake-up circuit a/open. Learn what this fault indicates and where to begin diagnosis.U301BControl Module Wake-up Circuit A LowCheck soonNetwork & Communication45–120 minutes for initial diagnosisU301B concerns control module wake-up circuit a low. Learn what this fault indicates and where to begin diagnosis.U301CControl Module Wake-up Circuit A HighCheck soonNetwork & Communication45–120 minutes for initial diagnosisU301C concerns control module wake-up circuit a high. Learn what this fault indicates and where to begin diagnosis.U301DControl Module Wake-up Circuit A PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU301D concerns control module wake-up circuit a performance. Learn what this fault indicates and where to begin diagnosis.U301EControl Module Wake-up Circuit B/OpenCheck soonNetwork & Communication45–120 minutes for initial diagnosisU301E concerns control module wake-up circuit b/open. Learn what this fault indicates and where to begin diagnosis.U301FControl Module Wake-up Circuit B LowCheck soonNetwork & Communication45–120 minutes for initial diagnosisU301F concerns control module wake-up circuit b low. Learn what this fault indicates and where to begin diagnosis.U3020Control Module Wake-up Circuit B HighCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3020 concerns control module wake-up circuit b high. Learn what this fault indicates and where to begin diagnosis.U3021Control Module Wake-up Circuit B PerformanceCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3021 concerns control module wake-up circuit b performance. Learn what this fault indicates and where to begin diagnosis.U3022Ignition Input Accessory/OffCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3022 concerns ignition input accessory/off. Learn what this fault indicates and where to begin diagnosis.U3023Control Module Input Power Circuit A - Ignition Input On/Start Circuit CorrelationCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3023 concerns control module input power circuit a - ignition input on/start circuit correlation. Learn what this fault indicates and where to begin diagnosis.U3024Control Module Input Power Circuit B - Ignition Input On/Start Circuit CorrelationCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3024 concerns control module input power circuit b - ignition input on/start circuit correlation. Learn what this fault indicates and where to begin diagnosis.U3025Control Module A Disable Circuit/OpenCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3025 concerns control module a disable circuit/open. Learn what this fault indicates and where to begin diagnosis.U3026Control Module A Disable Circuit LowCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3026 concerns control module a disable circuit low. Learn what this fault indicates and where to begin diagnosis.U3027Control Module A Disable Circuit HighCheck soonNetwork & Communication45–120 minutes for initial diagnosisU3027 concerns control module a disable circuit high. Learn what this fault indicates and where to begin diagnosis.