Why it helps
A free reference built from real workshop diagnostics rather than generic definitions, and an entry point into a free WrenchLane signup.
wrenchlane.com has free pages for individual fault codes, grouped by family, make and system. Each page shows what the code means, how often it has been seen across diagnostics run in WrenchLane and in how many separate workshops, which codes tend to appear with it, related codes and sometimes a worked video.
No account needed.
How to
- Open the page for a code, for example wrenchlane.com/en/fault-code/p0300
- Follow the related code links to similar codes
- Use the button on the page (for example 'Run P0300 against the car in front of you') to try WrenchLane free
Good to know
- The pages are built from anonymised, aggregated diagnostics run in WrenchLane; no workshop, customer or vehicle can be identified.
- The counts are a snapshot of WrenchLane diagnostics and are updated from time to time.
- Manufacturer-specific codes appear as companion codes but do not have their own page.
- Only a few codes have a worked video so far.
Related questions
Is there a free fault code tool I can use without an account?
Yes. guides.wrenchlane.com has free diagnostic guides for common codes and symptoms, and a Beta checker that matches a symptom or code to up to 3 published guides. wrenchlane.com also has a page per fault code built from diagnostics run in WrenchLane.
Learn more: WrenchLane Guides (diagnostic guides), Free symptom & DTC checker, Fault code pages on wrenchlane.com (fault-code cluster)
Are the public fault code pages built from my diagnostics?
They are built from anonymised, aggregated diagnostics run in WrenchLane; no workshop, customer or vehicle can be identified. Each fault code page shows how often the code was seen across those diagnostics and in how many separate workshops.
Learn more: Fault code pages on wrenchlane.com (fault-code cluster)
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