OBD-II Trouble Code Lookup

Search 9415 diagnostic trouble codes for what they mean, what causes them, and how to fix them.

How to use this site

  1. Read the code — connect an OBD-II scanner to your car's port, turn the key on, and note the code shown (it starts with P, C, B, or U).
  2. Look it up — enter the full code or a keyword like “catalyst” in the search box above.
  3. Review common causes — every code page lists the most frequent culprits for that exact code.
  4. Diagnose before you spend — follow the step-by-step guidance and confirm the fault with live data before replacing parts.

What is OBD Codes List?

OBD Codes List is a free, no-sign-up OBD-II trouble code lookup covering all 9415 generic SAE J2012 codes plus the most commonly searched manufacturer codes. Each page explains what the code means, how serious it is, what usually causes it, and a safe order of steps to check and fix it — written for DIYers without a factory service manual.

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