Support
Answers to common questions are below. If you need more help, email support@racemeasureapp.com.
Which OBD adapters work?
- ELM327-compatible adapters with Wi-Fi, for example Vgate Wi-Fi adapters.
- ELM327- or STN-compatible adapters with Bluetooth Low Energy (Bluetooth 4.0 or later).
Not supported: generic Bluetooth Classic adapters (often marked Bluetooth 2.0 or 3.0) and tools with their own protocol, such as the Autel AP200. Very cheap clones may lack some commands; then some modules may not answer.
How do I connect a Wi-Fi adapter?
- Plug the adapter into the OBD-II port (usually under the dashboard on the driver's side) and switch on the ignition.
- In iPhone Settings → Wi-Fi, join the adapter's network (V-LINK, WiFi_OBDII or similar).
- Open CarDiag AI and tap Connect to OBD → Wi-Fi → Find on Wi-Fi. If the adapter isn't found, enter its address manually (often 192.168.0.10, port 35000) and tap Use this address.
The adapter's network has no internet. For the AI features, keep mobile data on, or run the AI analysis after the scan once you're back on a network with internet; the report stays in the app.
How do I connect a Bluetooth adapter?
Don't pair the adapter in iPhone Settings. In the app, tap Connect to OBD → Bluetooth → Search for an OBD adapter. The search takes 10 seconds; then choose your adapter from the list, and the app checks that it answers. Allow Bluetooth access when iOS asks.
Which cars and modules can the app read?
Cars with an OBD-II/EOBD diagnostic port. "Engine only (OBD-II)" reads the standard engine data. "All available modules" searches for the modules that answer through the port and reads their fault codes over UDS or KWP2000. Which modules answer depends on the car, its gateway and your adapter, so CarDiag AI doesn't replace a dealer tool. A scan takes from under a minute to a few minutes.
How can I try the app without a car?
Use demo mode: tap Connect to OBD → Demo → Use demo, then Scan the car → All available modules. A built-in emulator answers like a car with several modules and sample fault codes, so you can explore the report and the other screens. No real car is involved. AI features work on the demo report too and use credits as usual.
What is free, and what does Pro include?
Free: reading codes, offline code meanings, scan history and demo mode. CarDiag Pro adds clearing codes, live gauges and PDF reports. Available Pro options and current prices are shown in the app before purchase. Credits for AI analysis and chat can be purchased separately.
How are AI credits charged?
- Credits for AI analysis and chat can be purchased separately in the app.
- Available packs and current prices are shown in the app before purchase. Your balance and usage are available in My account.
- A request that fails is not charged.
- Credits never expire. Any credits included with a Pro subscription are described in the app before purchase.
How do I restore purchases or move to a new iPhone?
Pro: on the Pro screen, tap Restore purchases while signed in with the same Apple Account. Credits: your balance is linked to a random account ID stored in iCloud Keychain. With iCloud Keychain on, the balance appears on your new iPhone automatically. If it doesn't, tap Restore purchases; if that doesn't help, email us the date and amount of your purchase from Apple's receipt email and we will help restore it.
How do I cancel the subscription or get a refund?
Cancel in Settings → your name → Subscriptions → CarDiag AI, at least 24 hours before the renewal date. Pro stays active until the end of the paid period. Refunds are handled by Apple: request one at reportaproblem.apple.com. We can't issue refunds ourselves.
Should I clear the fault codes?
Only after the fault has been inspected or repaired. Clearing doesn't fix anything: the code comes back if the fault is still there. It also deletes the freeze-frame data a workshop needs and resets the readiness monitors, so the car may fail an emissions inspection until it has completed its drive cycles. Permanent codes can't be cleared with a scan tool; the control unit removes them after a successful self-test.
Clear only with the car standing still and the ignition on. The clear starts right after you tap the button or ask for it in the chat; tap Cancel or Stop to stop it before the commands are sent. More in the Terms of Use.
The AI or voice input doesn't respond
AI features and voice input need an internet connection; with a Wi-Fi adapter, keep mobile data on. For voice input, allow microphone access in Settings → CarDiag AI → Microphone. On first use, the app asks for your consent to share data with the AI providers; without it, the AI features stay off.
What happens to my data?
Scan reports stay on your iPhone. For the AI features, data is sent to our server in the EU and processed by Anthropic and OpenAI, only after your consent. The details are in the Privacy Policy.
Contact support
Email support@racemeasureapp.com. Please include your iPhone model and iOS version, the app version, your adapter (brand, model, Wi-Fi or Bluetooth) and the car's make, model and year.
For scan problems, open the report, use Share the technical scan log and attach the file. The log contains your VIN and the raw scan data, so send it only to us.
RACEMEASURE LLC · Phone: +1 954 459 3962