OBD fault code library

Look up any P or U code to see what it means, what causes it, the parts involved and how it gets fixed.

Free on OBD DashX

Looking for real-world repair data?

OBD DashX shows which problems come with each code, how often they show up in other vehicles, and how to fix them — step by step.

  • Real-world fix data
  • How often it happens
  • Step-by-step repairs
Browse codes on OBD DashX No sign-up needed · available in 10 languages
U0503 /codes/dtcs/u0503
Communication Network System
U0505 /codes/dtcs/u0505
Communication Network System
U0506 /codes/dtcs/u0506
Communication Network System
U0507 /codes/dtcs/u0507
Communication Network System
U0508 /codes/dtcs/u0508
Communication Network System
U0509 /codes/dtcs/u0509
Communication Network System
U050B /codes/dtcs/u050b
Communication Network System
U050C /codes/dtcs/u050c
Communication Network System
U050D /codes/dtcs/u050d
Communication Network System
U050E /codes/dtcs/u050e
Communication Network System
U050F /codes/dtcs/u050f
Communication Network System
U0510 /codes/dtcs/u0510
Communication Network System
U0512 /codes/dtcs/u0512
Communication Network System
U0513 /codes/dtcs/u0513
Communication Network System
U0514 /codes/dtcs/u0514
Communication Network System

Search fault codes

Scan your own car

Read and clear fault codes, live data and service resets with the CaRPM app.