Get Started with CarX

Three simple steps. No mechanic needed. Works with any car made after 2004.

Download CarX

Get CarX free from the App Store. Works on iPhone and iPad running iOS 17 or later.

Plug In Your OBD-II Adapter

Every car made after 2004 (UK/EU) or 1996 (US) has an OBD-II port -- usually under the dashboard near the steering column, often behind a small cover. Plug your OBD-II adapter into this port. Turn your ignition on (engine running or ACC mode).

Need a dongle? Buy the CarX Approved OBD-II adapter here →

Connect in the CarX App

Open CarX, go to the Profile tab, and tap Connect OBD Device. CarX will scan for nearby adapters -- tap yours to pair. Once connected, live data streams instantly to your dashboard. That's it -- you're ready to go.

Choosing an OBD-II Adapter

Not all OBD adapters are created equal. Here's what to look for:

Best Choice

Bluetooth Low Energy (BLE)

BLE adapters are the most reliable with CarX. They connect faster, use less battery, and maintain a stable connection. Look for adapters that mention "BLE 4.0+" or "Bluetooth Low Energy".

Supported

Wi-Fi Adapters

Wi-Fi OBD adapters also work with CarX. They're common and widely available. The downside is they create their own Wi-Fi network, which means your phone disconnects from your regular Wi-Fi while connected.

Recommended adapters: Vgate iCar Pro (BLE), OBDLink MX+ (BLE), Veepeak OBDCheck (BLE), Streetwize SWOBD3 (BLE). These are well-tested and reliable.
Budget adapters: Cheap no-brand ELM327 clones (under £10) can work, but many use older Bluetooth Classic instead of BLE, or have counterfeit ELM327 chips that drop connections and give unreliable readings. If your adapter costs less than a coffee, expect issues.
Avoid: Very old adapters that only support Bluetooth 2.0 or serial connections. These won't work with modern iPhones.

Troubleshooting Connection Issues

"I can't find my adapter in the app"

Make sure your ignition is ON (engine running or ACC mode). The adapter needs power from the OBD port to broadcast its Bluetooth signal. Also check that Bluetooth is enabled in your iPhone Settings. If using a BLE adapter, it won't appear in the normal Bluetooth settings list -- it only shows up inside the CarX app.

"It connects but then disconnects straight away"

This is usually a cheap adapter issue. Budget ELM327 clones often have counterfeit chips that can't maintain a stable connection. Try moving your phone closer to the adapter (within 2 metres). If it keeps happening, you likely need a better quality BLE adapter.

"I'm getting no data or all zeros"

Check that the OBD adapter is fully seated in the port -- push it in firmly. Make sure your engine is running (not just ignition on). Some cars take 10-15 seconds to start sending data after connection. If you see all zeros for RPM and speed, your engine might be off.

"My adapter worked before but now it won't connect"

Unplug the OBD adapter, wait 10 seconds, plug it back in. In the CarX app, go to Profile and tap Disconnect, then Connect again. If that doesn't work, toggle Bluetooth off and on in your iPhone Settings. Some adapters need a power cycle after the car has been off for a while.

"My Wi-Fi adapter disconnects my internet"

This is normal for Wi-Fi OBD adapters -- your phone connects to the adapter's Wi-Fi network instead of your home/mobile network. CarX will still work for live data, but AI chat needs internet. For the best experience, use a BLE adapter instead, which doesn't affect your internet connection.

"Where is my OBD-II port?"

It's almost always under the dashboard on the driver's side, within arm's reach of the steering wheel. Look below the steering column -- sometimes behind a small plastic cover or flap. On some cars it's near the fuse box or centre console. Check your car's manual if you can't find it. If you're not confident plugging it in yourself, ask your local mechanic to do it for you -- it takes 10 seconds and any garage will be happy to help.

Predictive Car Health

CarX uses modern AI-driven analysis to build a real-time picture of your car's health. By continuously monitoring your vehicle's electronic sensors, CarX detects patterns and trends that predict problems before they leave you stranded.

When enough data is available, CarX provides predictive insights -- for example, spotting a battery that's slowly declining and warning you days before it fails, or detecting a coolant temperature pattern that suggests a developing issue. The more you drive with CarX connected, the smarter it gets about your specific car.

What CarX reads from your car:

Engine health -- RPM, load, coolant temperature, intake air temp
Battery voltage -- tracks decline over time, predicts failure before it happens
Fault codes (DTCs) -- reads confirmed, pending, and permanent faults with plain-English explanations
Fuel system -- fuel trims, pressure, efficiency patterns
Emissions -- oxygen sensors, catalytic converter efficiency

Every OBD-II adapter reads this data -- it's a universal standard:

All OBD-II adapters (BLE, Wi-Fi, or classic Bluetooth) read the same data from your car's onboard computer. The OBD-II port is a standardised connector fitted to every car sold in the UK and EU since 2004, and in the US since 1996. CarX works with any compliant adapter -- the difference between adapters is connection reliability, not data quality.

Important -- Please Read

CarX provides predictions and informational analysis only. All insights, health scores, and fault assessments are generated by AI based on OBD-II sensor data and should be treated as guidance, not a definitive diagnosis.

Always verify with a qualified mechanic. CarX predictions are a starting point -- not a replacement for professional inspection. Before making any repair decisions or safety judgements, consult a qualified, authorised mechanic.
OBD-II covers electronics only. It does not check brakes, tyres, suspension, bodywork, exhaust, steering, or any mechanical component. These require a physical inspection.
Predictions depend on available data. The accuracy of predictive analysis improves over time as more data is collected. Early predictions with limited data should be treated with extra caution.
Do not rely solely on CarX for safety-critical decisions. If your car feels unsafe, pulls to one side, makes unusual noises, or shows warning lights -- stop driving and seek professional help immediately regardless of what CarX shows.

AI Disclaimer: CarX uses artificial intelligence to analyse vehicle data and generate responses. AI can make mistakes. Responses may be inaccurate, incomplete, or misleading. Always check important information independently and do not make safety, financial, or repair decisions based solely on AI-generated advice. CarX AI output is provided "as is" with no guarantees of accuracy or reliability.

CyberSecAI Ltd accepts no liability for actions taken based on CarX readings, predictions, or recommendations. CarX is a diagnostic aid, not a certified vehicle inspection service. Use of CarX does not replace an MOT, manufacturer service, or professional mechanic assessment.

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