What can a car diagnostic test tell you?

Bradley Jando | Friday 2nd October 2020 11:20am

 Technician making notes on a clipboard

If youíve ever experienced issues with your car or had a warning light flash up on your carís dashboard and wondered what the problem might be - chances are, you could benefit from a car diagnostic test.

Even though most technicians and mechanics recommend taking your car in for a diagnostic check at least once a year, many drivers donít take their cars in for diagnostic tests which could end up saving them money in the long run.

A contributing factor may be that the many drivers not being sure what vehicle diagnostics can tell you about your vehicle, what it covers or how beneficial it is.

Car diagnostics can help to identify issues early

A car diagnostic test can be the difference between having to pay for repairs and spotting problems with your car early on before they become a bigger problem.

A typical diagnostic test will inform you about a range of issues that your vehicle could be experiencing with engine management, transmission, ignition coils, throttle, exhaust, brakes and more. Typically diagnostic tests will focus around the engine, however, depending on the vehicle, the diagnostics will offer information on other aspects such as lights, tyres and comfort controls as well.

Some of the more specific issues that it can identifu include low engine coolant levels, an excessive build-up in the combustion engine, poor performance from the fuel injection system, poor ignition timing, ignition coil firing failure and particularly low or high rpm levels.

How do car diagnostic tests work?

Diagnostic tests use the carís engine control unit, which can be found in most modern cars. The ECU utilises sensors throughout the vehicle to identify issues as they occur, anything from increased engine temperature to whether the ignition coils are firing. This generates a specific error code that is then indicated on your carís dashboard by the corresponding warning light.

However, while the dashboard can let you know that thereís a problem, the total extent of the issue is something that can only be gauged by specialist vehicle diagnostics equipment which reads the error code that trained technicians can use to identify the issue.

Why should I get a car diagnostic test?

Engine diagnostics and general diagnostic tests can help to identify multiple issues before they have a severe impact on the performance of your vehicle. By taking your car in for an annual vehicle diagnostics test, you can uncover minor issues that wonít otherwise be spotted by your carís ECU until itís too late.

Additionally, if youíre conducting a check of a used car, the vehicle ECU can store previous notifications from the manufacturer as well as historic data of the carís performance - providing you with all the information you need to make an informed inspection.

With the standard diagnostics test duration being around an hour, itís a small amount of time to ensure that your vehicle is running with minimal issues and to identify any potential problems that could cost you in the long run.

Car diagnostic tests with Kwik Fitís state-of-the-art Bosch equipment

Here at Kwik Fit, we have state of the art Bosch equipment at our disposal which our expert technicians use to identify and suggest any required repairs that you might need.

Our specialist equipment will inspect lights and comfort controls in addition to the standard diagnostic aspects. The Bosch diagnostic equipment also resets service lights, adjusts headlamp levels as well as testing and adjusting braking systems (where an electronic handbrake is present).

Book online for your free engine diagnostics check or contact your local Kwik Fit centre.

Any facts, figures and prices shown in our blog articles are correct at time of publication.

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