Heavy-Duty Fault Code Lookup
Search by SPN, FMI, OEM code, manufacturer, system, component, symptom, glossary term, or phrase. Search runs entirely in your browser and does not store your query.
Type at least 2 characters to search verified records.
FAQ
Does search use a backend or database?
No. The page loads a static JSON index and filters it in the browser.
What can I search for?
You can search SPN, FMI, OEM code, manufacturer, component, system, symptom, glossary term, or phrase.
Why are some example codes missing from search?
Records that need sources, are unverified, or do not pass publishing guards are excluded from search and sitemap.