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
U2531 /codes/dtcs/u2531
Communication Network System
U2533 /codes/dtcs/u2533
Communication Network System
U2534 /codes/dtcs/u2534
Communication Network System
U2535 /codes/dtcs/u2535
Communication Network System
U2536 /codes/dtcs/u2536
Communication Network System
U2537 /codes/dtcs/u2537
Communication Network System
U2538 /codes/dtcs/u2538
Communication Network System
U2539 /codes/dtcs/u2539
Communication Network System
U253B /codes/dtcs/u253b
Communication Network System
U253C /codes/dtcs/u253c
Communication Network System
U253D /codes/dtcs/u253d
Communication Network System
U253E /codes/dtcs/u253e
Communication Network System
U253F /codes/dtcs/u253f
Communication Network System
U2540 /codes/dtcs/u2540
Communication Network System
U2541 /codes/dtcs/u2541
Communication Network System

Search fault codes

Scan your own car

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