Is the car diagnostic app free to use?

Yes. The Motor Vehicle Expert diagnostic app is free to use in a web browser.

Can the app check dashboard warning lights?

Yes. The app includes dashboard warning light guidance for common lights such as engine, battery, oil, coolant, ABS, airbag, brakes and tyre pressure.

Does the app replace a mechanic?

No. The app gives general guidance to help drivers understand possible faults, but serious vehicle problems should be checked by a qualified mechanic.

Free UK Vehicle Diagnostics

Free Car Diagnostic App For UK Drivers

Use the Motor Vehicle Expert diagnostic app to check dashboard warning lights, vehicle symptoms, common OBD fault codes, possible causes, safe-to-drive advice and MOT implications in plain English.

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What The App Does

Vehicle Checks In One Simple Tool

The app is designed for everyday UK drivers and workshop-style checks. It helps you understand what a warning light or symptom may mean before you decide what to do next.

Dashboard Warning Light Lookup

Search common warning lights including engine, battery, oil, coolant, ABS, airbag, brake and tyre pressure lights.

Vehicle Symptom Checker

Check symptoms such as overheating, loss of power, misfire, smoke from exhaust, clicking noises, rough idle and car not starting.

OBD Fault Code Lookup

Look up common OBD fault codes such as P0300, P0171, P0420, P0101 and related diagnostic meanings.

MOT-Aware Guidance

See whether a fault or warning light may affect an MOT test, especially where brakes, emissions, ABS, airbags, tyres or warning lights are involved.

Built For Real Drivers

Plain-English Diagnostic Help

Many drivers see a warning light and do not know whether they should stop, keep driving, book a mechanic or prepare for an MOT issue. This app gives simple guidance written in practical language, not confusing technical jargon.

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Useful Guides

Related Diagnostic Guides

These guides support the app with more detailed explanations for common UK car faults.

Engine Management Light Guide Battery Warning Light Meaning Car Warning Lights Meaning UK Brake Warning Light On While Driving Coolant Warning Light On Oil Warning Light On And Off Can ABS Light Fail MOT? Can Airbag Light Fail MOT? Car Won’t Start Diagnosis Guide Engine Misfire Symptoms And Causes Car Losing Power When Accelerating Exhaust Smoke Colour Guide

Important Note

The App Gives Guidance, Not A Final Diagnosis

The diagnostic app is designed to help you understand possible causes and next checks. It does not replace a physical inspection, professional diagnostic scan or qualified mechanic. If your car has red warning lights, brake problems, overheating, heavy smoke, loss of steering, loss of braking or unsafe driving behaviour, stop safely and get professional help.

FAQ

Diagnostic App Questions

Is the diagnostic app free?

Yes. The app is free to open and use in your web browser.

Can it tell me if my car is safe to drive?

It gives general safe-to-drive guidance based on the symptom or warning light selected. If the issue feels serious, get the car checked before driving further.

Can it help with MOT problems?

Yes. The app includes MOT-aware guidance for warning lights and faults that may affect brakes, emissions, ABS, airbags, tyres and other testable items.