Data coverage

A code index built from manufacturer communications filed with NHTSA in the United States. Vehicle-specific and enhanced codes are included; this is not a list of universal definitions.

How to use this information

This reference uses manufacturer communications received by the US NHTSA during 1995–2026. It includes passenger vehicles, commercial vehicles and some vehicle-equipment records. A document mention is a research lead, not proof that every listed vehicle has the fault. Confirm the complete code, engine, production range and market in the manufacturer's service information.

Repeated filings are grouped only when make, bulletin number, publication date and complete summary agree. Original record numbers are retained. Older publications remain available, and an explicit later version is shown when established. Pre-1994 vehicle associations are separated from default results; an unspecified year does not mean all model years apply.

Source wording can vary by vehicle and suffix. It is shown as written, not as a universal diagnosis.

CarObdCode preserves 3,395 historical directory records (3,394 distinct base codes) and links a separate NHTSA-derived index of 6,142 observed codes. Their union is 8,030 base codes. These counts do not mean every entry has a universal verified definition. The 32 source-backed reference explanations have twelve editorial language editions. Historical labels retain manufacturer distinctions, including both P1441 entries. Raw manufacturer documents and vehicle associations have their own scope.

These explanations are editorial summaries of the linked manufacturer material. PDF page numbers count from the first file page. Original publications are in English; translations are reference aids. A cited edition is not a claim that it is the manufacturer's latest instruction.

NHTSA manufacturer communications ↗

Updated · 2026-10-28