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.

Check soon 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 7129–7152 of 8256

Most searched first

U01ACLost Communication With Hybrid/EV Battery Interface Control Module MCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01AC concerns lost communication with hybrid/ev battery interface control module m. Learn what this fault indicates and where to begin diagnosis.U01ADLost Communication With Hybrid/EV Battery Interface Control Module NCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01AD concerns lost communication with hybrid/ev battery interface control module n. Learn what this fault indicates and where to begin diagnosis.U01AELost Communication With Hybrid/EV Battery Interface Control Module OCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01AE concerns lost communication with hybrid/ev battery interface control module o. Learn what this fault indicates and where to begin diagnosis.U01AFLost Communication With Hybrid/EV Battery Interface Control Module PCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01AF concerns lost communication with hybrid/ev battery interface control module p. Learn what this fault indicates and where to begin diagnosis.U01B0Lost Communication With Battery Monitor ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01B0 concerns lost communication with battery monitor module. Learn what this fault indicates and where to begin diagnosis.U01B1Lost Communication With Particulate Matter Sensor BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01B1 concerns lost communication with particulate matter sensor b. Learn what this fault indicates and where to begin diagnosis.U01B2Lost Communication With Planetary Gear Set Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01B2 concerns lost communication with planetary gear set control module. Learn what this fault indicates and where to begin diagnosis.U01B3Lost Communication With Brake Blending ActuatorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01B3 concerns lost communication with brake blending actuator. Learn what this fault indicates and where to begin diagnosis.U01B4Lost Communication With Brake System Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01B4 concerns lost communication with brake system control module b. Learn what this fault indicates and where to begin diagnosis.U01B5Lost Communication With Catalyst Heater Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01B5 concerns lost communication with catalyst heater control module. Learn what this fault indicates and where to begin diagnosis.U01B6Lost Communication With Fuel Heater Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01B6 concerns lost communication with fuel heater control module. Learn what this fault indicates and where to begin diagnosis.U01B7Lost Communication With Switch Input Module “A”Check soonNetwork & Communication45–120 minutes for initial diagnosisU01B7 concerns lost communication with switch input module “a”. Learn what this fault indicates and where to begin diagnosis.U01B8Lost Communication With Switch Input Module “B”Check soonNetwork & Communication45–120 minutes for initial diagnosisU01B8 concerns lost communication with switch input module “b”. Learn what this fault indicates and where to begin diagnosis.U01B9Lost Communication With Switch Input Module “C”Check soonNetwork & Communication45–120 minutes for initial diagnosisU01B9 concerns lost communication with switch input module “c”. Learn what this fault indicates and where to begin diagnosis.U01BALost Communication With Park Lock/Pawl Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01BA concerns lost communication with park lock/pawl control module. Learn what this fault indicates and where to begin diagnosis.U01BBLost Communication With Battery Charger Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01BB concerns lost communication with battery charger control module b. Learn what this fault indicates and where to begin diagnosis.U01BCLost Communication With Charge Air Cooler Coolant Pump BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01BC concerns lost communication with charge air cooler coolant pump b. Learn what this fault indicates and where to begin diagnosis.U01BDLost Communication With DC/DC Converter Control Module CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01BD concerns lost communication with dc/dc converter control module c. Learn what this fault indicates and where to begin diagnosis.U01BELost Communication with Drive Motor A Clutch ActuatorCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01BE concerns lost communication with drive motor a clutch actuator. Learn what this fault indicates and where to begin diagnosis.U01BFLost Communication with Battery Management Control ModuleCheck soonNetwork & Communication45–120 minutes for initial diagnosisU01BF concerns lost communication with battery management control module. Learn what this fault indicates and where to begin diagnosis.U0200Lost Communication With Door Control Module BCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0200 concerns lost communication with door control module b. Learn what this fault indicates and where to begin diagnosis.U0201Lost Communication With Door Control Module CCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0201 concerns lost communication with door control module c. Learn what this fault indicates and where to begin diagnosis.U0202Lost Communication With Door Control Module DCheck soonNetwork & Communication45–120 minutes for initial diagnosisU0202 concerns lost communication with door control module d. Learn what this fault indicates and where to begin diagnosis.U0203Lost Communication With Door Control Module ECheck soonNetwork & Communication45–120 minutes for initial diagnosisU0203 concerns lost communication with door control module e. Learn what this fault indicates and where to begin diagnosis.