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.

Network & Communication 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

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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 649–672 of 1228

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U049BInvalid Data Received From Tachograph ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU049B concerns invalid data received from tachograph module. Learn what this fault indicates and where to begin diagnosis.U049CInvalid Data Received From Battery Charger Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU049C concerns invalid data received from battery charger control module a. Learn what this fault indicates and where to begin diagnosis.U049DInvalid Data Received From Glow Plug Control Module 2Check soonNetwork & Communication45–120 minutes for initial diagnosisU049D concerns invalid data received from glow plug control module 2. Learn what this fault indicates and where to begin diagnosis.U049EInvalid Data Received From Direct Ozone Reduction Catalyst Temperature SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU049E concerns invalid data received from direct ozone reduction catalyst temperature sensor. Learn what this fault indicates and where to begin diagnosis.U049FInvalid Data Received From Transmission Range Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU049F concerns invalid data received from transmission range control module. Learn what this fault indicates and where to begin diagnosis.U04A0Invalid Data Received From Engine Coolant Pump Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04A0 concerns invalid data received from engine coolant pump control module. Learn what this fault indicates and where to begin diagnosis.U04A1Invalid Data Received From Hybrid/EV Battery Interface Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU04A1 concerns invalid data received from hybrid/ev battery interface control module a. Learn what this fault indicates and where to begin diagnosis.U04A2Invalid Data Received From Hybrid/EV Battery Interface Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04A2 concerns invalid data received from hybrid/ev battery interface control module b. Learn what this fault indicates and where to begin diagnosis.U04A3Invalid Data Received From Hybrid/EV Battery Interface Control Module CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04A3 concerns invalid data received from hybrid/ev battery interface control module c. Learn what this fault indicates and where to begin diagnosis.U04A4Invalid Data Received From Particulate Matter Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU04A4 concerns invalid data received from particulate matter sensor a. Learn what this fault indicates and where to begin diagnosis.U04A5Invalid Data Received From Hybrid/EV Battery Interface Control Module ECheck soonNetwork & Communication45–120 minutes for initial diagnosisU04A5 concerns invalid data received from hybrid/ev battery interface control module e. Learn what this fault indicates and where to begin diagnosis.U04A6Invalid Data Received From Hybrid/EV Battery Interface Control Module FCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04A6 concerns invalid data received from hybrid/ev battery interface control module f. Learn what this fault indicates and where to begin diagnosis.U04A7Invalid Data Received From Hybrid/EV Battery Interface Control Module GCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04A7 concerns invalid data received from hybrid/ev battery interface control module g. Learn what this fault indicates and where to begin diagnosis.U04A8Invalid Data Received From Hybrid/EV Battery Interface Control Module HCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04A8 concerns invalid data received from hybrid/ev battery interface control module h. Learn what this fault indicates and where to begin diagnosis.U04A9Invalid Data Received From Hybrid/EV Battery Interface Control Module ICheck soonNetwork & Communication45–120 minutes for initial diagnosisU04A9 concerns invalid data received from hybrid/ev battery interface control module i. Learn what this fault indicates and where to begin diagnosis.U04AAInvalid Data Received From Hybrid/EV Battery Interface Control Module JCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04AA concerns invalid data received from hybrid/ev battery interface control module j. Learn what this fault indicates and where to begin diagnosis.U04ABInvalid Data Received From Hybrid/EV Battery Interface Control Module KCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04AB concerns invalid data received from hybrid/ev battery interface control module k. Learn what this fault indicates and where to begin diagnosis.U04ACInvalid Data Received From Hybrid/EV Battery Interface Control Module LCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04AC concerns invalid data received from hybrid/ev battery interface control module l. Learn what this fault indicates and where to begin diagnosis.U04ADInvalid Data Received From Hybrid/EV Battery Interface Control Module MCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04AD concerns invalid data received from hybrid/ev battery interface control module m. Learn what this fault indicates and where to begin diagnosis.U04AEInvalid Data Received From Hybrid/EV Battery Interface Control Module NCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04AE concerns invalid data received from hybrid/ev battery interface control module n. Learn what this fault indicates and where to begin diagnosis.U04AFInvalid Data Received From Hybrid/EV Battery Interface Control Module OCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04AF concerns invalid data received from hybrid/ev battery interface control module o. Learn what this fault indicates and where to begin diagnosis.U04B0Invalid Data Received From Hybrid/EV Battery Interface Control Module PCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04B0 concerns invalid data received from hybrid/ev battery interface control module p. Learn what this fault indicates and where to begin diagnosis.U04B1Invalid Data Received From Battery Monitor ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04B1 concerns invalid data received from battery monitor module. Learn what this fault indicates and where to begin diagnosis.U04B2Invalid Data Received From Particulate Matter Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU04B2 concerns invalid data received from particulate matter sensor b. Learn what this fault indicates and where to begin diagnosis.