CarDiag AI: OBD2 Scanner
Check Engine Codes Explained
Only for iPhone
Free · In‑App Purchases · Designed for iPhone. Not verified for macOS.
iPhone
Scan all available modules for free. Try AI analysis and find out what to check next. Credits for AI analysis are available separately in the app.
CarDiag AI turns your iPhone and an ELM327-compatible OBD adapter into a fault code reader with an AI mechanic. Read the codes, see what they mean and get a clear plan for what to check first.
HOW IT WORKS
1. Plug a Wi-Fi or Bluetooth LE adapter (for example, Vgate) into the OBD-II port and switch on the ignition.
2. Connect in the app and choose a scan: engine only (OBD-II) or all modules that answer.
3. Open the report and ask the AI mechanic what it means for your car.
FEATURES
• Fault codes from every module that answers, such as engine, transmission, ABS or airbags, over OBD-II, UDS and KWP2000
• Offline meanings for 9,348 generic codes in English, German and Russian
• Offline VIN decoding: make, country and, where the VIN encodes it, model year; model and engine for many European cars
• AI fault analysis: likely causes, what to check yourself, what the workshop should check and whether it looks safe to drive
• Chat with the AI mechanic by text or voice; it can ask the app to read more data from the car (read-only)
• Claude and GPT models, from quick answers to deep analysis
• Live gauges: up to three OBD values in real time
• PDF reports to share with your workshop
• Clear fault codes on your command, with a readback of what was really cleared
• Scan history and saved AI analyses on your iPhone
• My account: support ID and credit balance
• Demo mode: explore the app without a car
GOOD TO KNOW
CarDiag AI is not a dealer tool. Which modules answer depends on the car, its gateway and your adapter. Manufacturer-specific codes often have no public definition; when the AI interprets one, the app says so. Bluetooth Classic adapters that only show up in iPhone Settings cannot be used by iPhone apps.
PRO AND CREDITS
Free: reading codes, offline meanings, scan history and demo mode.
CarDiag Pro unlocks clearing codes, live gauges and PDF reports. Subscription and lifetime options are available.
Try AI analysis for free. Credits for AI analysis can be purchased separately in the app.
Pro Monthly is an auto-renewable subscription. Payment is charged to your Apple Account when you confirm the purchase. The subscription renews automatically unless you cancel it at least 24 hours before the end of the current period; the renewal is charged within 24 hours before the period ends. Manage or cancel it in your Apple Account settings.
PRIVACY
No sign-up, no ads, no tracking. Scan reports and completed AI analyses are saved on your iPhone. With your consent, AI features send data through our servers to Anthropic and OpenAI. Our privacy policy explains how this data is processed and stored.
SAFETY
Don't use the app while driving. AI answers are for information and don't replace a qualified mechanic. Clearing codes resets the readiness monitors, so have the fault inspected first.
Terms of Use: https://racemeasureapp.com/cardiag/terms
Privacy Policy: https://racemeasureapp.com/cardiag/privacy
Apple Standard EULA: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Improved connectivity for AI features. If your connection drops, you can resume retrieving an analysis result. Completed AI analyses are saved with your scan history and remain available when you reopen the app.
The developer, RaceMeasure LLC, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Linked to You
The following data may be collected and linked to your identity:
- Purchases
- User Content
- Identifiers
- Usage Data
- Diagnostics
- Other Data
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- RaceMeasure LLC
- Size
- 15.3 MB
- Category
- Utilities
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
English and 2 more
- English, German, Russian
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- CarDiag Pro Monthly $4.99
- 1,000 AI Credits $9.99
- 100 AI Credits $0.99
- CarDiag Pro Lifetime $39.99
- 500 AI Credits $4.99
- 2,500 AI Credits $24.99
- Copyright
- © 2026 RACEMEASURE LLC