// Phone-based diagnostics

Bluetooth OBD2 scanners: which kind you actually need

A €45 dongle and a €219 dongle can look almost identical. What differs is what they can talk to, whether they work with your phone, and what you pay for after the box. Here is the honest breakdown.

The three kinds

 Generic adapterFull-system app scannerBrand specialist
ReadsEngine and emissionsEvery moduleEvery module, one make
Service resetsRarelyYesYes, for that make
CodingNoSomeYes, that's the point
AppThird-party appsThe maker's own appThe maker's or a dedicated app
Watch foriPhone supportPer-brand licencesOnly works on its make

1. Generic adapters: the cheap way to read engine codes

These are ELM327-type adapters. Paired with a phone app, they read and clear engine fault codes, show live engine data and tell you whether emissions monitors are ready. For a check-engine light, that's often all you need; the code reader guide walks through it.

What they generally can't do: reach ABS, airbag, transmission or body modules, or run service resets. If your warning light isn't the engine light, a generic adapter usually can't help.

2. Full-system app scanners: every module from your phone

These come with the maker's own app and manufacturer software. They read every module, show system-specific live data, and run service resets like oil service, electronic parking brake retraction and steering angle calibration. Some can also run bidirectional active tests.

ScannerWhat to knowPrice
Autel AP200Full-system for one car brand of your choice included; more brands are added in the app€75
KONNWEI KDIAGFull-system with active tests on supported vehicles€89
Thinkdriver ProFull-system scan and common resets€129
ThinkDiag 2Active tests and CAN FD; manufacturer coverage is licensed per brand each year€219
Read the licence before you buy. App scanners often include coverage for a set of brands or a set period, with more available as in-app purchases. That isn't a trick, but it matters: decide which makes you'll work on, then check what's included. See the ThinkDiag guide for how its brand licences work.

3. Brand specialists: the deepest route for one make

If all your cars are one make, a specialist tool goes further than a general scanner, especially for coding.

Ford or Mazda? Their deep route is FORScan, which works best over a USB adapter: see the FORScan guide.

iPhone or Android

Android works with almost any Bluetooth adapter. iPhone is pickier: apps generally can't connect to adapters using classic Bluetooth. For iPhone, choose an adapter that supports Bluetooth Low Energy or Wi-Fi, or a scanner whose own app is on the App Store. Wi-Fi adapters are the other iPhone-friendly route, at the cost of borrowing the phone's Wi-Fi while connected. If you're on iPhone, check the product listing says iOS before you buy.

Bluetooth or a handheld?

A phone-based scanner is smaller, cheaper for the same depth, and easier to update. A handheld or tablet doesn't depend on your phone and is handier in a workshop. If you'd rather not use your phone at all, see the buyer's guide for handhelds and tablets.

Questions people actually ask

Why won't my adapter connect to my iPhone?
Most often it uses classic Bluetooth, which iPhone apps can't use. You need a BLE or Wi-Fi adapter, or a scanner whose own app supports iOS.
Can a Bluetooth scanner turn off the ABS or airbag light?
A full-system scanner can read and clear those codes on supported cars. A generic engine-only adapter can't reach those modules. Clearing a code doesn't fix the fault behind it, so read the code first.
Can I leave it plugged in?
Many adapters have a sleep mode, but if the car will sit for a while, unplug it to avoid draining the battery.
Do I need a subscription?
Generic adapters work with free or one-off apps. Full-system and brand tools may charge for extra brands, coding or yearly updates. Each tool above lists what to check.

Phone-based scanners in the shop.

From €43 for engine codes to €219 for full-system active tests. Shipped free, 2-year warranty.

See the range → Which tool do I need?