Diagnostic library

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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.

Check soon U · Network Clear all

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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 409–432 of 1223

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U02B8Lost Communication With Rear Radar Module CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B8 concerns lost communication with rear radar module c. Learn what this fault indicates and where to begin diagnosis.U02B9Lost Communication With Rear Radar Module DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02B9 concerns lost communication with rear radar module d. Learn what this fault indicates and where to begin diagnosis.U02BALost Communication With Hybrid/EV Electronics Coolant Pump BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02BA concerns lost communication with hybrid/ev electronics coolant pump b. Learn what this fault indicates and where to begin diagnosis.U02BBLost Communications with EVAP System Purge PumpCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02BB concerns lost communications with evap system purge pump. Learn what this fault indicates and where to begin diagnosis.U02BCLost Communication With Localization and Mapping ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02BC concerns lost communication with localization and mapping module. Learn what this fault indicates and where to begin diagnosis.U02BDLost Communication With Night Vision Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02BD concerns lost communication with night vision control module. Learn what this fault indicates and where to begin diagnosis.U02BELost Communication With Trailer Backup Assist Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02BE concerns lost communication with trailer backup assist control module. Learn what this fault indicates and where to begin diagnosis.U02BFLost Communication With Interior Lighting Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02BF concerns lost communication with interior lighting control module b. Learn what this fault indicates and where to begin diagnosis.U02C0Lost Communication With Active Radiator Air Flow Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU02C0 concerns lost communication with active radiator air flow control module a. Learn what this fault indicates and where to begin diagnosis.U02C1Lost Communication With Hybrid/EV Electronics Coolant Pump CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU02C1 concerns lost communication with hybrid/ev electronics coolant pump c. Learn what this fault indicates and where to begin diagnosis.U0300Internal Control Module Software IncompatibilityCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0300 concerns internal control module software incompatibility. Learn what this fault indicates and where to begin diagnosis.U0301Software Incompatibility With ECM/PCMCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0301 concerns software incompatibility with ecm/pcm. Learn what this fault indicates and where to begin diagnosis.U0302Software Incompatibility With Transmission Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0302 concerns software incompatibility with transmission control module. Learn what this fault indicates and where to begin diagnosis.U0303Software Incompatibility With Transfer Case Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0303 concerns software incompatibility with transfer case control module. Learn what this fault indicates and where to begin diagnosis.U0304Software Incompatibility With Gear Shift Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0304 concerns software incompatibility with gear shift control module a. Learn what this fault indicates and where to begin diagnosis.U0305Software Incompatibility With Cruise Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0305 concerns software incompatibility with cruise control module. Learn what this fault indicates and where to begin diagnosis.U0306Software Incompatibility With Fuel Injector Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0306 concerns software incompatibility with fuel injector control module. Learn what this fault indicates and where to begin diagnosis.U0307Software Incompatibility With Glow Plug Control Module 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU0307 concerns software incompatibility with glow plug control module 1. Learn what this fault indicates and where to begin diagnosis.U0308Software Incompatibility With Throttle Actuator Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0308 concerns software incompatibility with throttle actuator control module. Learn what this fault indicates and where to begin diagnosis.U0309Software Incompatibility With Alternative Fuel Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0309 concerns software incompatibility with alternative fuel control module. Learn what this fault indicates and where to begin diagnosis.U030ASoftware Incompatibility With Evaporative Emission System Leak Detection Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU030A concerns software incompatibility with evaporative emission system leak detection control module. Learn what this fault indicates and where to begin diagnosis.U030BSoftware Incompatibility With Glow Plug Control Module 2Check soonNetwork & Communication45–120 minutes for initial diagnosisU030B concerns software incompatibility with glow plug control module 2. Learn what this fault indicates and where to begin diagnosis.U030CSoftware Incompatibility With Reductant Quality ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU030C concerns software incompatibility with reductant quality module. Learn what this fault indicates and where to begin diagnosis.U030DSoftware Incompatibility With NOx Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU030D concerns software incompatibility with nox sensor a. Learn what this fault indicates and where to begin diagnosis.