Modern cars have a very high presence of electronic components. The entire system is managed by a series of control units : from the engine control unit, the heart of the vehicle, to the various control units responsible for managing various components and functions, such as the automatic transmission, stability control, climate control, infotainment and so on.

In practice, an electronic control unit continuously checks the correct functioning of the car or a specific part of the system. The efficiency of the car therefore passes through thousands of checks that each control unit performs continuously.

 

However, it can happen that something jams, and then the system signals an anomaly to the driver by turning on a warning light on the instrument panel . When taking the car to the workshop, the trusted auto electrician or mechanic will use the most suitable diagnostic tool to understand what is happening inside our car. This tool, through the OBD ( On Board Diagnostic ) port, will be able to read the information made available by the various control units, allowing us to understand if all the system components, sensors and actuators, are working correctly, to allow the Automotive professional to identify and resolve the problems present.

 

Thanks to diagnostic tools, it is possible to understand what errors are hidden behind the presence of a warning light on the dashboard. The classic “engine warning light” on can in fact contain an infinite number of problems, from the simplest to the most complicated to solve.

 

The quality of the tool and the operator's ability to understand the type of error therefore determine the success or failure of the intervention in the workshop. In fact, if a professional tool allows you to identify 100% of the problems reported by a control unit, with an "economic" or do-it-yourself diagnostic tool you can run into problems reading and interpreting the information, even leading to incorrect solutions.

Our advice is to go to the garage whenever our car has a malfunction warning light on.

 

In fact, there are huge differences between a professional diagnostic tool and an amateur or cheap diagnostic tool, in addition to the price.

• The first large macro area of analysis is the variety of readings . An economic tool could in fact be created to support only some types of vehicles, or to recognize only some control units or types of malfunctions. On the contrary, a professional tool is generally enabled to recognize all vehicles and also all the control units present on board.
• Professional tools also have the ability to archive the information retrieved from the control units. In this way, everything that has been detected over time is archived in a sort of database linked to our car. Cheap or non-professional diagnostic tools do not usually have this feature and therefore do not allow you to maintain a historical archive.
• A very important possibility available to professional diagnostic tools is linked to WiFi connection and the possibility of being updated . In fact, if we buy a certain cheap diagnostic tool today, it will probably not be updated for the cars that will be marketed from tomorrow onwards. Professional diagnostic tools, on the other hand, have the ability to connect to the Internet and update themselves to support future cars that will be produced.
• As a final aspect, we also point out that professional diagnostic systems usually have an independent form of power supply . In simpler terms, they can be connected via cable and plug to the home or workshop electrical network, or to work with their own battery. Amateur systems, on the other hand, are powered by the car battery; this aspect may seem trivial, but in truth it is not as a reading or diagnosis of the system could take a long time and in the event that there is a serious problem it is always better to save the car battery and rely on an external power supply.

Here are the main features that distinguish professional diagnostic tools from amateur or cheap diagnostic tools. The general advice is to always rely on professionals in the sector who can perform a diagnosis and an in-depth analysis using professional tools.

 

But there are situations in which even a non-professional tool can be useful . Motor enthusiasts or more experienced drivers can use these tools to get an idea of a problem that has suddenly appeared in their car and communicate it to their mechanic, as a sort of remote pre-diagnosis.

 

If the engine light comes on, perhaps while you are traveling or away from a workshop, by connecting a DIY diagnostic tool you can obtain some basic information about the anomaly. Generally you get one or more errors identified by a DTC code ( Diagnostic Trouble Code ), which consists of a sequence of alphanumeric characters, such as P0380 .

 

On these pages we illustrate the most frequent error codes, with a description of the causes and possible solutions. This information is presented for educational and informative purposes only, and in no case can it replace a correct diagnosis and intervention at an accredited workshop.