What Does a Car Diagnostics Test Do?

At one time, when there was a problem with a car, you would check through manuals or books in the hope of finding an idea of what the issue was.  Or take it to your local garage offering car repairs in West Sussex and they would have gone through their books and manuals.  Nowadays, there is a much simpler way – car diagnostics tests.  Let’s take a look at what they do.

Warning lights and the ECU

If there’s a warning light illuminated on your dashboard, this is your car’s way of telling you something is wrong.  But understanding what that is, what needs to be done and how urgently it needs doing is a little harder to tell from a blinking light.

However, the majority of modern cars have an on-board computer called an Engine Control Unit or ECU.  This monitors the performance of the vehicle and is connected to a network of sensors all around the car.  This means it can sense things from the engine temperature being too high to low levels of fluid or even problems with brakes or other key systems.

There are hundreds of errors codes that the ECU can produce and the only way to understand and translate them is with diagnostic tools.  So while a light might tell you generally that something is wrong, you often need to visit a garage with the right equipment to find out the full extent of what it means.

How the diagnostic check works

There are lots of different versions of diagnostic equipment and we use the latest, state of the art models to be able to communicate with the ECU.  Our trained technicians are able to look at the information provided by the ECU to the diagnostic tool and then be able to tell you exactly what is needed.

Say the ‘check engine’ light came on – but there are hundreds of parts in the engine so how do you know what is wrong?  The ECU will send the exact error code to the diagnostic tool when connected to explain exactly what the problem is.  The same can apply if there’s a problem with the tyres, emissions, lights and even comfort controls in the car.

Acting on the information

Armed with this information, we can then look to fix the problems and get the car running smoothly as well.  While there are problems that the ECU doesn’t pick up – cracks in windscreens are one example – they can diagnose many of the problems that a car can experience.

Diagnostic tools are not used as part of MOTs generally but if you visit our Worthing garage and we find a problem that causes an MOT fail, we sometimes use the diagnostic equipment to further delve into the nature of the problem.  This means we can quickly get the car through its retest and get you the certificate you need.

Lights on the dashboard are rarely just a loose wire – they are a sign that something is wrong.  That’s why it is worth going to your local car diagnostics garage to find out the root of any problems as soon as they appear.