Help and frequently asked questions
Answers to the questions we are asked most often about DiagAuto AI. If yours is not here, write to us: contact@diagautoai.eu.
Before you start
Is my vehicle compatible?
Almost all cars have had an OBD2 port since the late 1990s or early 2000s, depending on the regulations of each country. The information available then depends on the vehicle (make, model, year, engine) and on the adapter: not all vehicles provide all measurements, and some control units only respond to the manufacturer's tools.
Which adapter do I need?
An ELM327-type or compatible OBD2 adapter, using Bluetooth, Bluetooth Low Energy (BLE) or Wi‑Fi. We have gathered the models we have tried on the page Which OBD2 adapter to choose, and the steps to follow on Connect an adapter.
Is the app available on iPhone?
Not for now: DiagAuto AI is designed for Android.
Can I try it without an adapter?
Yes. Demo mode presents the app with simulated data, without a car or an adapter.
Connecting to the car
The adapter does not appear in the list
A classic Bluetooth adapter must first be paired in the phone's Bluetooth settings (code often 0000 or 1234), like a headset. A BLE adapter is not paired: plug it in, turn the ignition on, then tap “Search for BLE adapters” in the app. A Wi‑Fi adapter requires the phone to be connected to its Wi‑Fi network; then enter its IP address in the app (often 192.168.0.10).
The adapter is connected but “the car is not responding”
Check that the ignition is on, with the engine off or running, and that the adapter is pushed all the way into the port; a light usually comes on on it. Some very cheap adapters do not support all protocols, especially on cars from before 2008. If the problem persists, the “Report a problem” button below the error message prepares a report with the technical log; you are the one who sends it, and it helps us understand what happened.
The control unit scan finds none, or very few
On older cars that do not communicate over CAN, scanning the other control units does not apply: the app says so. On a recent car, a very low result often comes from the adapter: a Wi‑Fi clone found only 2 control units on a BMW where a vLinker read 18. See the page Which OBD2 adapter to choose.
With a Wi‑Fi adapter, the AI does not respond
The phone is connected to the adapter's Wi‑Fi network, which has no Internet access. The app then uses mobile data to reach the AI: check that it is turned on.
Fault codes and artificial intelligence
Confirmed, pending, permanent codes: what is the difference?
A confirmed code has turned on the engine warning light. A pending code has been detected once but is not yet confirmed: it may disappear or be confirmed on the next trip. A permanent code stays in memory even after clearing, until the car has itself checked that the fault has gone.
What exactly does “Clear codes” do?
The app sends the standard OBD2 clear command to the engine control unit, only after your confirmation, and first offers to save the report. Clearing repairs nothing: if the fault is still there, the warning light will come back. The emissions checks go back to “not ready” until the car has run them again, which can be a problem at the roadworthiness test. No reprogramming, ever: the app does not change any vehicle setting.
Can the AI be wrong?
Yes. It does not see your car and measures nothing itself: its answers are leads to help you understand, not a certified diagnosis. Have a professional check before any repair or purchase of a part, and stop safely if the problem affects the brakes, steering, airbags or a red warning light. The thumbs-down below an answer flags it to us.
What information does the AI receive?
The code and its official meaning, the measurements read just before if the car provides them, the data frozen at the time of the fault and the vehicle information (make, model, year, engine, mileage). Never your name, your registration number or your location. The details are on the page What the AI does and in the privacy policy.
AI credits and purchases
What is an AI credit?
An AI credit entitles you, as you choose, to the explanation of a fault code, a diagnosis (based on a symptom or on monitoring), a service light reset procedure, or a conversation of 10 answers over 24 hours. The cost is shown on each button. The credit is deducted on request and automatically returned if the service cannot answer (service unreachable, error or empty answer).
What can you do without buying anything?
Read and clear engine codes, read the codes of the other compatible control units, view the emissions checks, the real-time sensors and the VIN, use demo mode. On first installation, you receive 10 complimentary AI credits; after that, if your balance falls back to 0, you receive 1 complimentary AI credit per month for as long as it stays at 0.
What are the offers?
Premium is a one-time purchase, with no subscription: PDF reports, several vehicles, full history and 100 AI credits granted once. The Breakdown pack (40 credits) and Enthusiast pack (100 credits) have no expiry date. The Pro subscription, monthly or yearly, adds 300 AI credits per month, up to 40 per day. The content and price of each offer are shown in the app before any purchase.
My purchase does not appear
Features and credits are added as soon as our server has verified the purchase with Google, usually within a few seconds. Without a connection, they arrive at the next launch or with “Restore my purchases”. A pending payment is taken into account as soon as Google confirms it; if a purchase cannot be validated, Google refunds you automatically within 3 days. If nothing changes, write to us with the Google Play order number (it starts with “GPA.”).
I am changing phones
Premium and the Pro subscription are linked to your Google account: on the new phone, sign in with the same account and use “Restore my purchases”. AI credits, however, are linked to the phone: in the app's store, “Changing phones” shows your recovery code; enter it on the new phone. The old code then stops working. This code is the only way to transfer your credits: we cannot retrieve it for you, so keep it safe.
How do I cancel the Pro subscription?
At any time, at no cost, in Google Play (Payments & subscriptions, then Subscriptions) or with “Manage my subscription” in the app. The subscription remains active until the end of the paid period. Uninstalling the app does not cancel the subscription. Pro can be used on only one phone at a time.
Can I get a refund?
Purchases go through Google Play, which applies its own rules (Google Play, Help, Request a refund). In addition, on simple request we refund a duplicate purchase, or a purchase that does not work on your phone or your vehicle because of a problem on our side. Write to contact@diagautoai.eu with the “GPA.” order number; we do our best to reply as quickly as possible. The details are in the terms of use and sale.
Your data
Do I need to create an account?
No. There is no account, no advertising, no usage statistics, and your location is never read. The data read from your vehicle stays on your phone; it only leaves it when you use the AI, look up your vehicle's model online, send us feedback, share a report, or if you have agreed to share technical logs. Only your AI credits account is held by our server, under an anonymous identifier.
How do I delete my data?
A saved vehicle, diagnosis or adapter can be deleted in the app; everything is erased by uninstalling it. For your credits account, the “Request deletion of my data” button prepares the necessary email. The complete steps are on Delete your data.
What is technical log sharing?
If you accept it, after each diagnosis the app sends us the technical exchanges between the adapter and the car, to help us better understand the vehicles we know poorly. No name, no full VIN, no location; the logs are deleted after 12 months. The choice can be changed at any time in Settings and changes nothing in how the app works.
Contact us
How do I report a problem?
In the app: Settings, then “Report a problem”; the thumbs-down below an AI answer; or the “Report a problem” button shown below a failure message. The feedback screen shows you what will be sent (vehicle, codes, technical log without full VIN) and you are the one who sends it.
How do I write to you?
At contact@diagautoai.eu. State the vehicle (make, model, year, engine), the adapter model, the Android version and what happened. Do not send a registration number or a full VIN. We reply within 7 days. The publisher's contact details are in the legal notice.