Diagnostic interface or diagnostic scanner - what about vehicle diagnostics?

Despite the fact that the latest cars are crammed with electronics and their design is more complicated than before, diagnosing a malfunction should not be difficult. This even requires a basic diagnostic interface that can be used to read errors in the control unit. However, there are quite a few such devices, some of them offer a minimum number of options, while others offer everything possible. How to find the right one for you? So what do you need to know about them? What would be the right choice?

How does the vehicle diagnostic interface work?

The secret lies in the OBDII connector (“on-board diagnostics”). It is responsible for transmitting signals from the vehicle self-diagnosis control unit to the output device. The obligation to install this type of socket has been introduced in cars manufactured since 1996 in the USA, and in Europe since 2001. Therefore, all cars since 2000 are usually equipped with such a connector. However, one socket is not enough to read the signals.

Car diagnostics with a tester

The equipment that allows you to read the signals sent to the OBDII connector is a diagnostic interface that works according to the ELM327 protocol. This is a small trapezoidal cube that is inserted into an outlet. Both the connector itself and the plug are made in such a way as not to confuse the sides of connecting the equipment. Therefore, no user of the vehicle should have problems installing it.

The next device you need is a smartphone, tablet, laptop, or other device that accepts the Bluetooth signal sent by elm327. On the other hand, it is necessary to place software on it that will read the signals and inform the driver about errors visible in the car's computer. However, this is not the only tool that can be used to diagnose cars.

What is the ELM327 protocol? 

The ELM327 protocol is a basic and fairly versatile type of device that works well as a diagnostic scanner. Displays basic information such as error codes or drive data. However, to get more information and have a greater impact on vehicle diagnostics, you can choose other interfaces. Most often they are dedicated to specific brands or concerns.

Which autotester should you choose?

If you want to get an idea of ​​the smallest details, choose a dedicated diagnostic interface. 

1. For example, for cars of the VAG group, i.e. Audi, Seat, Skoda, Volkswagen, you will need a name module. 
2. For BMW vehicles, these are, for example, Carly and K+DCAN. 
3. If you are an FCA car owner, the best choice would be OBD2 VAG KKL or FIATECUSCAN.

What can be checked through the diagnostic interfaces?

The advanced capabilities of paid diagnostic programs and specialized interfaces exceed the capabilities of universal solutions. Using the diagnostic scanner, you can, among other things:

• monitor engine operating parameters such as coolant temperature, oil temperature, air/fuel mixture injection rate, turbocharger boost pressure, lambda probe readings, or battery voltage;
• reading the list of errors caused by violations detected by the sensors and deleting them;
• measure the performance of the drive unit - power, torque, instantaneous fuel consumption;
• Diagnose the operation of individual systems, for example, air conditioning.
• adjust the operation of some systems - the time the light is turned on after the door is closed, the sensitivity of the rain sensors;
• maintain engine performance while driving.

Types of connection for car diagnostics. Wireless diagnostic interface

The choice is not too great, because there are devices on the market that work in Bluetooth, Wi-Fi and cable systems. Wireless are most often used for basic diagnostic work. They are convenient and easy to use, do not require wiring. Opinions about the wireless diagnostic interface are generally good, and drivers who use it on a daily basis are satisfied.

However, often wired versions allow you to read data even faster, and in some cases get additional information that is not available for universal wireless versions. So if you want to regularly analyze engine performance and get basic information, the wireless model is all you need. For more serious diagnostics, choose cable copies.

What program to use for the diagnostic tester?

There are many apps for Android, iOS and Windows. They can be divided into free and paid. Very often these are the same programs with the same names, for example, Torque, Car Scanner, Piston, Dash Command, OBDeleven, OBD Mary, OBD Harry Scan. In free applications, the diagnostic interface will display little information, but most often it will allow you to remove errors that appear in the controller and carefully check them. Paid. Extended versions are designed to measure more parameters and enable detailed analysis.

Why is it worth investing in an interface and doing car diagnostics yourself?

First, having a diagnostic interface is very practical. At any time while driving, you can monitor the behavior of the engine and catch the causes of possible malfunctions. 

Diagnostic interfaces as a way to save money? 

The diagnostic interface will save you a decent amount of money. Imagine a situation where the “check engine” icon appears on the dashboard. It may indicate various problems and errors. The easiest way is to get to the nearest car repair shop, where you will pay 50-10 euros for the service of connecting a diagnostic computer and erasing errors, and what if in a week or two, and worst of all, on the same day after restarting the engine, does the problem return? After several such visits, the cost of the interface pays off.

A personal diagnostic interface will allow you to reset the error yourself. You can also use it to constantly monitor engine behavior, performance and calibrate systems yourself without visiting a mechanic. Of course, it is good to have at least basic mechanical and electromechanical knowledge in order to change the settings in the car in this way.

Diagnostic scanners and interfaces

Automotive scanners, i.e. diagnostic scanners, are made for mechanics and demanding people. How do they differ from diagnostic interfaces?

Most diagnostic scanners are equipped with:

• autonomous;
• the ability to read data from any vehicle;
• candles for the vast majority of cars
• and allow extensive intervention in the systems of a given vehicle. 

Very often, car scanners also have extensive software, a complete and constantly updated database of error codes and other information about vehicles. With diagnostic scanners, you have more options for troubleshooting and troubleshooting. However, the downside is the unequivocally higher purchase price and often the need to renew the subscription.

Which interface to choose - ELM327 or another?

If you are not interested in digging into the back streets of a computer controller, then the ELM327 universal diagnostic tester is the right choice. It will provide you with basic error information and basic engine parameters. The price of such a device is several tens of zlotys, if we talk about the cheapest versions. Plus a free phone app and you'll be able to diagnose problems in your car for next to nothing. If the basics don't suit you and you're looking for more options, then use a dedicated diagnostic scanner and a paid, well-designed app. Then you can find out a lot of additional information about your vehicle and, importantly, change a lot in it. For mechanics, professional diagnostic interface kits are recommended.