Diagnostic library

Find an OBD2 code

Search the code from your scanner, then narrow the library by system, severity, or code family.

9,253 diagnostic guides

Sort

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

Quick browse

Choose a vehicle system

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 937–960 of 1228

Most searched first

U065DLost Communication With Air Intake ActuatorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU065D concerns lost communication with air intake actuator. Learn what this fault indicates and where to begin diagnosis.U065ELost Communication With Ram Air ActuatorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU065E concerns lost communication with ram air actuator. Learn what this fault indicates and where to begin diagnosis.U065FLost Communication With Left Rear Temperature Actuator ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU065F concerns lost communication with left rear temperature actuator a. Learn what this fault indicates and where to begin diagnosis.U0660Lost Communication With Left Rear Temperature Actuator BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0660 concerns lost communication with left rear temperature actuator b. Learn what this fault indicates and where to begin diagnosis.U0661Lost Communication With Right Rear Temperature Actuator ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0661 concerns lost communication with right rear temperature actuator a. Learn what this fault indicates and where to begin diagnosis.U0662Lost Communication With Right Rear Temperature Actuator BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0662 concerns lost communication with right rear temperature actuator b. Learn what this fault indicates and where to begin diagnosis.U0663Lost Communication With Rear Mode ActuatorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0663 concerns lost communication with rear mode actuator. Learn what this fault indicates and where to begin diagnosis.U0664Lost Communication With Rear HVAC Air Cutoff ActuatorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0664 concerns lost communication with rear hvac air cutoff actuator. Learn what this fault indicates and where to begin diagnosis.U0665Lost Communication With Fuel Rail Pressure Sensor Bank 2Check soonNetwork & Communication45–120 minutes for initial diagnosisU0665 concerns lost communication with fuel rail pressure sensor bank 2. Learn what this fault indicates and where to begin diagnosis.U0666Lost Communication With Reductant Pressure SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0666 concerns lost communication with reductant pressure sensor. Learn what this fault indicates and where to begin diagnosis.U0667Lost Communication With Engine Oil Temperature Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0667 concerns lost communication with engine oil temperature sensor a. Learn what this fault indicates and where to begin diagnosis.U0668Lost Communication With Engine Oil Level Sensor CircuitCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0668 concerns lost communication with engine oil level sensor circuit. Learn what this fault indicates and where to begin diagnosis.U0669Lost Communication With EGR Sensor DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0669 concerns lost communication with egr sensor d. Learn what this fault indicates and where to begin diagnosis.U066ALost Communication With EGR Sensor ECheck soonNetwork & Communication45–120 minutes for initial diagnosisU066A concerns lost communication with egr sensor e. Learn what this fault indicates and where to begin diagnosis.U066BLost Communication With Turbocharger/Supercharger Bypass Valve B Position SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU066B concerns lost communication with turbocharger/supercharger bypass valve b position sensor. Learn what this fault indicates and where to begin diagnosis.U066CLost Communication With Exhaust Heat Exchanger Bypass Valve Actuator BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU066C concerns lost communication with exhaust heat exchanger bypass valve actuator b. Learn what this fault indicates and where to begin diagnosis.U066DLost Communication With Charge Air Cooler Temperature Sensor Bank 1Check soonNetwork & Communication45–120 minutes for initial diagnosisU066D concerns lost communication with charge air cooler temperature sensor bank 1. Learn what this fault indicates and where to begin diagnosis.U066ELost Communication With Charge Air Cooler Temperature Sensor Bank 2Check soonNetwork & Communication45–120 minutes for initial diagnosisU066E concerns lost communication with charge air cooler temperature sensor bank 2. Learn what this fault indicates and where to begin diagnosis.U066FLost Communication With Low Pressure Fuel System SensorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU066F concerns lost communication with low pressure fuel system sensor. Learn what this fault indicates and where to begin diagnosis.U0670Lost Communication With Fuel Temperature Sensor ACheck soonNetwork & Communication45–120 minutes for initial diagnosisU0670 concerns lost communication with fuel temperature sensor a. Learn what this fault indicates and where to begin diagnosis.U0671Lost Communication With Fuel Temperature Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0671 concerns lost communication with fuel temperature sensor b. Learn what this fault indicates and where to begin diagnosis.U0672Lost Communication With Engine Coolant PumpCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0672 concerns lost communication with engine coolant pump. Learn what this fault indicates and where to begin diagnosis.U0673Lost Communication With Ion Sense ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0673 concerns lost communication with ion sense module. Learn what this fault indicates and where to begin diagnosis.U0674Lost Communication With Wastegate Position Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0674 concerns lost communication with wastegate position sensor b. Learn what this fault indicates and where to begin diagnosis.