How are OBD-II codes formatted?
Quick Answer
Base codes use P/B/C/U and hexadecimal characters; preserve any additional scanner suffix and manufacturer context.
A conventional displayed base code has five characters: P, B, C or U followed by a 0-3 range character and three hexadecimal characters, which may include A-F. P, B, C and U identify broad system families. Standardized, manufacturer-controlled and reserved assignments depend on the code range; the second character alone is not a complete classification rule. Scanners can append failure-type bytes, such as U0100:87. Preserve those extra characters and verify the manufacturer interpretation.