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A LEADING INDEPENDENT GARAGE NEAR SHEFFORD, BEDFORDSHIRE

What Does a Car Diagnostic Test Tell You?

What Does a Car Diagnostic Test Tell You?

What’s the Purpose of the Diagnostics Test?

Diagnostic testing for cars first arrived in the UK in the 1980s, although early prototypes were prohibitively expensive. It wasn’t until the mid 90s that diagnostic machines became affordable and were available to garages like Country Vehicles. Now they’re part of our fixtures and fittings but that doesn’t mean everyone understands what they do. ‘What does a car diagnostic test tell you?’ is a question we get asked regularly, so here’s our answer.


The Car Diagnostic Test

Not so long ago, when your car broke down a mechanic would have to poke around in the engine to find the cause. Since those days cars have become increasingly complex machines involving multiple computers which are monitored by sensors located throughout the vehicle. These are all co-ordinated by the ECU; the Engine Control Unit. This is like the nerve centre of your car. If a fault is detected by a sensor, it’s reported to the ECU.

The first the driver is likely to know of any fault is when the warning light on the dashboard flashes. This means that an error code has been sent to the EDU which needs checking out at a garage. A garage technician will use a diagnostics machine to retrieve the code and attend to the problem.

How Do Technicians Use the Diagnostic Test?

The car diagnostic test is the equivalent of a health check for your vehicle. What does a car diagnostic test tell you? It can expose problems with your car’s brakes, engine, exhaust, steering and transmission. It’s also able to locate performance issues with the throttle, air flow, lights, fuel injector, coolant and ignition coils.

Your car’s technician is able to retrieve data regarding the fault in your car by using a diagnostic machine. What diagnostics won’t tell you is what’s causing the problem. Your technician will need to use their skills and experience to determine that, and the nature of the solution.

What are the Benefits?

Prior to complex diagnostics, vehicles tended to end up in the garage once they’d either broken down, or experienced a major problem. Now the attention prompted by dashboard lights is largely preventive as problems are detected long before major repairs are required. Diagnostics are also used by manufacturers to send notifications, and to store information about the service history of the vehicle.

The 5 major benefits of a diagnostic test are:

  1. Preventive action in place of costly repairs
  2. Vehicle maintained at peak performance
  3. Accurate error reporting for all major components
  4. Updated service history available in digital form
  5. Your vehicle is safely maintained at all times

Diagnostic Testing at Country Vehicles Shefford

Country Vehicles is an independent garage based in Shefford, South Bedfordshire. Our diagnostics checks are fast, efficient and they’re carried out by a team of skilled technicians. They investigate fault alerts and carry out any remedial actions required. We would recommend a diagnostics check annually, with your car servicing. You should also book in if a dashboard light comes on, you sense there’s something wrong, or you’re buying a used car.


Would you like to book in a diagnostic check? Call CVS today on 01234 381555 today, or book online.