AutoDTCs is an independent technical reference for OBD-II and manufacturer-specific diagnostic trouble codes. We cover SAE-standard codes, OEM-specific codes (Toyota, Hyundai, VAG, BMW, Mercedes, Peugeot, and others), and failure-type-byte (FTB) suffix variants that most DTC sites don’t document.
What makes our articles different
Most DTC reference sites publish the SAE standard definition, a generic list of “possible causes”, and a repair-shop lead form. We go further:
- Real diagnostic reports as source material. Every article is informed by the same type of scan-tool output a professional technician reads — Autel MaxiSys, Launch X431, Bosch KTS, PSA Diagbox. The codes, freeze-frame data, and vehicle context come from real-world reports, not rewritten search results.
- OEM service-data procedures. For model-specific articles (such as Honda Insight P0962 or upcoming brand-variant guides), we work from vehicle-specific OEM diagnostic procedures — the exact test sequences, PCM pin numbers, resistance specifications, and ground-point references a dealer technician would follow. Readers get the real diagnostic flow, not a generic template with the vehicle name substituted in.
- SAE J2012 compliance. Every code page references the SAE J2012 standard for the generic definition, then expands into manufacturer-specific meaning where applicable.
- FTB-variant coverage. Toyota’s B0021:11 and B0021:13 are different faults with different diagnostic paths — we cover them together, in one article, with clear distinction. Most reference sites conflate them or skip FTB coverage entirely.
- European repair pricing context. Labour rates, parts costs, and workshop norms in the European market — not US-only estimates converted poorly.
- Related-code cross-links. Every article surfaces codes that commonly appear together (P0171 with P0172, P0335 with P0340, and so on), so readers can work through a full system diagnosis rather than chasing one code at a time.
Editorial process
- Source data. Diagnostic reports come from field scan-tool exports — real vehicles with real fault codes logged in the ECU, TCM, ABS, SRS, body, and network modules. We import the raw reports, deduplicate FTB variants, and research each code before writing.
- Research. Each code is cross-referenced against the SAE J2012 standard, publicly available manufacturer technical service bulletins, NHTSA recall records, and manufacturer service information. For manufacturer-specific codes we verify the brand-specific meaning against at least one field diagnostic report.
- Drafting. Articles follow a consistent structure: Quick Answer → What It Means → Theory of Operation → Symptoms → Common Causes → Diagnosis Steps → Fixes → Repair Costs → Related Codes → FAQ. Diagnosis steps include specific measured values (voltages, resistances, live-data ranges) wherever the fault pattern has a numeric threshold.
- Review. Articles are checked for technical accuracy against the source data and updated when field evidence changes. The “Last updated” date on each article reflects the most recent review cycle.
- Corrections. If you find an error — a circuit voltage range wrong for your year/market, a missing common cause, a mislabeled component — use our contact form to report it. We review every submission and update articles with confirmed corrections within seven days.
AI-assisted, human-reviewed
AutoDTCs uses AI as a writing tool to produce comprehensive, consistent content at scale. Every article covers the same diagnostic depth, follows the same structure, and gets the same editorial treatment. This is a deliberate choice: it’s how we can cover more than 2,500 codes — including manufacturer-specific variants most sites skip — while maintaining per-article depth.
Every article is written against real diagnostic source data, not generated from the code number alone. We disclose the AI-assisted workflow because transparency matters: you deserve to know how the content you’re reading was produced. The diagnostic information itself is sourced, referenced, and reviewable.
What we don’t do
- No affiliate-driven part recommendations. We reference repair manuals and diagnostic tools we use in our own work. We don’t recommend specific replacement parts based on commission structures.
- No gated content. Every article is free to read, without registration, email signup, or paywalls.
- No reader-data resale. We use Google Analytics and Google Search Console for aggregate traffic reporting only. We don’t maintain a customer database, don’t run cross-site behavioural tracking beyond what GA collects, and don’t sell reader data to third parties.
- No unverified claims about vehicle defects. We describe fault patterns and diagnostic logic. We don’t make legal or warranty claims about specific manufacturers or models.
Independence and trademarks
AutoDTCs is not affiliated with, endorsed by, or sponsored by any vehicle manufacturer, scan-tool maker, or repair chain. All trademarks referenced in articles — manufacturer names, tool brands, software names — belong to their respective owners. We reference them to explain diagnostic context, not to claim association.
Sister site: VIN Decoder
We also operate vindecoder.site — a free VIN decoder built on the NHTSA public API for vehicle specifications, recalls, complaints, investigations, and safety ratings. When a DTC article discusses a recall or a vehicle-specific defect, we cross-link to the corresponding vindecoder.site page so you can check your VIN directly.
Contact
- Corrections or technical questions: use our contact form. Every submission is read by the editorial team.
- Press or partnership inquiries: use the contact form with “press” in the subject line.
Educational purpose
The information on AutoDTCs is provided for general educational purposes. Vehicle systems vary significantly by manufacturer, model, year, engine variant, and installed options. A diagnostic trouble code may have different meanings or diagnostic procedures depending on the vehicle. AutoDTCs does not replace professional diagnosis, manufacturer service manuals, or certified repair advice. If you are unsure about a diagnosis or repair, consult a qualified automotive technician or an authorised service provider.