Welcome to C15-OBD

Before you get started, please read this important notice.

AI Diagnostic — No Reader Needed

AI Diagnostic doesn't need an OBD-II reader: enter your fault codes or describe your symptoms and get step-by-step repair guidance instantly. It's part of C15-OBD Premium, which starts with a 7-day free trial.

No Liability

We accept no liability for any damage caused to your vehicle or any other property while using this app. The app is used entirely at your own risk.

ContactConnect

Contact us

Questions about connecting a reader, a fault code you need a second opinion on, a bug to report, or a vehicle you'd like to see covered — send us a message and we'll get back to you.

Send us a message

We usually reply within 1–2 working days.

Before you write

  • • Can't connect? The Connection Guide covers Bluetooth readers step by step.
  • • Fault code questions: include your make, model, year, engine and the exact code — the AI Diagnostic tool will also give you an instant walkthrough.
  • • Subscription and billing queries are handled through your account settings, and we can help here too.