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.

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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 121–144 of 1228

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U011ALost Communication With Exhaust Gas Sensor Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU011A concerns lost communication with exhaust gas sensor module a. Learn what this fault indicates and where to begin diagnosis.U011BLost Communication With Rocker Arm Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU011B concerns lost communication with rocker arm control module a. Learn what this fault indicates and where to begin diagnosis.U011CLost Communication With Rocker Arm Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU011C concerns lost communication with rocker arm control module b. Learn what this fault indicates and where to begin diagnosis.U011DLost Communication With All Wheel Drive Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU011D concerns lost communication with all wheel drive control module. Learn what this fault indicates and where to begin diagnosis.U011ELost Communication With Throttle Actuator B Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU011E concerns lost communication with throttle actuator b control module. Learn what this fault indicates and where to begin diagnosis.U011FLost Communication With V2X ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU011F concerns lost communication with v2x module. Learn what this fault indicates and where to begin diagnosis.U0127Lost Communication With Tire Pressure Monitor ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0127 means Lost Communication With Tire Pressure Monitor Module. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.U012ALost Communication With Chassis Control Module ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU012A concerns lost communication with chassis control module a. Learn what this fault indicates and where to begin diagnosis.U012BLost Communication With Chassis Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU012B concerns lost communication with chassis control module b. Learn what this fault indicates and where to begin diagnosis.U012CLost Communication With Active Vibration Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU012C concerns lost communication with active vibration control module. Learn what this fault indicates and where to begin diagnosis.U012DLost Communication With Generator A Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU012D concerns lost communication with generator a control module. Learn what this fault indicates and where to begin diagnosis.U012ELost Communication With Camshaft Position Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU012E concerns lost communication with camshaft position control module. Learn what this fault indicates and where to begin diagnosis.U012FLost Communication With Generator B Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU012F concerns lost communication with generator b control module. Learn what this fault indicates and where to begin diagnosis.U0131Lost Communication With Power Steering Control ModuleUrgentNetwork & Communication1–3 hours for initial diagnosisU0131 means Lost Communication With Power Steering Control Module. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.U013CLost Communication With Accelerator Pedal ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU013C concerns lost communication with accelerator pedal module. Learn what this fault indicates and where to begin diagnosis.U013DLost Communication With Vacuum Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU013D concerns lost communication with vacuum sensor a. Learn what this fault indicates and where to begin diagnosis.U013ELost Communication With Vacuum Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU013E concerns lost communication with vacuum sensor b. Learn what this fault indicates and where to begin diagnosis.U013FLost Communication With Pedestrian Alert Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU013F concerns lost communication with pedestrian alert control module. Learn what this fault indicates and where to begin diagnosis.U0146Lost Communication With Gateway ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0146 means Lost Communication With Gateway A. Review likely symptoms, causes, safety considerations, and a sensible diagnostic order.U014ALost Communication With Battery Energy Control Module CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU014A concerns lost communication with battery energy control module c. Learn what this fault indicates and where to begin diagnosis.U014BLost Communication With Hybrid/EV Battery Inductive Charging ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU014B concerns lost communication with hybrid/ev battery inductive charging module. Learn what this fault indicates and where to begin diagnosis.U014CLost Communication With Battery Energy Control Module DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU014C concerns lost communication with battery energy control module d. Learn what this fault indicates and where to begin diagnosis.U014DLost Communication with Mirror Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU014D concerns lost communication with mirror control module b. Learn what this fault indicates and where to begin diagnosis.U014ELost Communication With Multi-axis Acceleration Sensor Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU014E concerns lost communication with multi-axis acceleration sensor module b. Learn what this fault indicates and where to begin diagnosis.