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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 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 1225–1228 of 1228

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U0147Lost Communication With Gateway BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0147 means Lost Communication With Gateway B. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.U0148Lost Communication With Gateway CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0148 means Lost Communication With Gateway C. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.U0149Lost Communication With Gateway DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0149 means Lost Communication With Gateway D. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.U0150Lost Communication With Gateway ECheck soonNetwork & Communication45–120 minutes for initial diagnosisU0150 means Lost Communication With Gateway E. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.