OBD2 Scanner — Functions, Costs, and Tips

The terms OBD2 and OBD scanner are one that the average motorist may hear on a casual visit to an automotive repair center. For enthusiasts, this has a rather more elaborate meaning as it refers to the OBD (On-Board Diagnostics) standard that is integral towards understanding various parameters of a car’s systems.

So what is an OBD2 scanner? OBD2 scanners connect to OBD2 devices or cellphones with installed apps, typically via an OBD2 adapter cable. OBD2 scanners can range from €50 for basic models, and venture upwards of four figures for professional-level equipment that is used by high-end repair centers. OBD2 offers different levels of functionality, ranging from basic error code reading and display, to diagnostics, all the way to coding and re-flashing, depending on your scanner and reader or mobile app.

Let us take you on a journey through the nuances of OBD. Whether you are a regular driver or car enthusiast, you will get some new knowledge by the end of this article.

The History of OBD

First of all, let us explain what OBD means in more detail. OBD is the abbreviation for on-board diagnostics. OBD2 refers to the second generation of the on-board diagnostic system.

OBD, or on-board diagnostics is the system in a car that controls and monitors all the important control devices, offering data access to workshops and any individual with the requisite hardware and software. The crucial part of OBD is its ability to inform the reader of any defects or abnormal behaviors. When the system detects an error or abnormal functionality of a system under its purview, it stores a requisite error code in memory and illuminates a lamp on the instrument panel. This is typically called the “Check Engine” light. The user of the vehicle will take it to a repair center where the code can be read and the fault identified. The system is also used by authorities such as the TUV, for emission control.

OBD 1 — The Predecessor

OBD1 was conceptualized in the USA as a response towards efforts to reduce air pollution caused by the increasing prevalence of the automobile across major cities. California led the push to “keep the air clean” with the California Air Resources Board (CARB) introducing stricter emission limits for gasoline vehicles in 1988. Compliance just when brand new was not enough — the vehicle was required to comply for its lifetime. So, an electronic self-monitoring system had to be developed to allow compliance checks at any point; hence the emergence of OBD1. A signal light alerted the user of an abnormal condition. Other states adopted it in 1994. However, OBD1’s biggest failing was non-standardization, where automakers created and implemented their own systems, causing nightmares for repair centers that had to hold multiple scanners in order to read various systems.

OBD2 — The Current Standard

In 1994, CARB mandated by regulation that all new motor vehicles from 1996 onwards must contain the newly developed OBD2 system, which would utilize a standardized interface. In this way, not only were emissions regulations monitored, but the entire exhaust-influencing system with the various processes in a vehicle would be under its purview. The standardization resulted in a streamlined experience to read out fault codes.

OBD2 made it across the pond to Europe by 2000, with the Euro III emissions standards which similarly dictated that emissions errors had to be indicated by a warning light on the dashboard and error codes recorded by the vehicle. Since 2001, the OBD2 interface has been a regulation for all vehicles with Otto engines (petrol/gas engines). Diesel vehicles came under these regulations commencing in 2004.

The new standard made life much easier for repair centers, as well as enthusiasts. Running an OBD scan can be costly in terms of time as well as money, and most people are unaware that there are a large number of OBD2 scanners for private usage, enabling the end-user to conduct error analysis themselves with a reader and mobile app.

What Is an OBD2 Scanner?

The OBD2 scanner is the interface between the reader and mobile app to facilitate troubleshooting and fault diagnosis on the vehicle. The OBD2 port is a universal one that can typically be found in the driver’s area. In some instances, it may be difficult to find as it may lie beneath the dashboard or behind the steering column. A quick online search with your vehicle’s exact make and model can help.

Why Do We Use an OBD2 Scanner?

Once you have located the OBD2 port and connected the scanner, code-reading and troubleshooting can commence. The ignition switch must be set to the “ON” position but it is not necessary to start the engine. Upon first-time use, the attached reader or mobile app will require vehicle data such as make, model, year of manufacture, and other information to be input, and might also require the identification number which can be found in the vehicle registration document. Following this, reading of the error memory takes place. The OBD2 scanner accesses the vehicle control unit and analyzes the data. Most data may not be relevant, but the system typically scans all data. Once the scan has concluded, the device produces a list of error codes that are currently affecting the vehicle, as well as information about existing faults. Some error codes can be ambiguous, in which case, you may still need to visit a workshop.

Warning: Some scanners allow you to not only read the fault memory, but edit and delete as well. This sort of activity is risky and should be only performed by professionals at workshops, or experienced enthusiasts. Incorrect operation can result in the control unit being blocked or corrupted, with repairs in the thousands!

  What is an OBD2 Scanner?

Which Codes Do OBD2 Scanners Read?

Standard error codes are utilized by all manufacturers, and typical enthusiast-level scanners will only read these for private use, unless one is using a special scanner and reader from the vehicle manufacturer themselves.

Error codes are structured according to a uniform principle: one letter and four numbers. Professional-level devices provide additional information about general vehicle functions, such as defective or non-functional lights. These results are typically not displayed with a commercially available adapter for private use. The error codes of these connectors only contain information from the sensors and electronics from the following areas:

  • Powertrain (Code “P” = Powertrain)
  • Chassis (code “C” = chassis)
  • Body (code “B” = body)
  • Networks (code “U” = User Network)

Reading this letter allows the user to determine the location of the error. The next digit relates to the error code group.

  • 0 manufacturer-independent
  • 1 manufacturer-specific

Moving on to the third digit, this informs about the vehicle assemblies pertaining to the error.

  • 0 refers to the overall system
  • 1 stands for the secondary air / air mixture preparation
  • 2 is a fault in the fuel system
  • 3 concerns the ignition system / misfiring
  • 4 quantifies all additional systems for emission monitoring
  • 5 designates the cruise / idle speed control
  • 6 relates to the computer and its input / output signals
  • 7 stands for the transmission

Digits four and five are the consecutive numbers for the individual component that is providing the error.

An OBD2 scanner is not only an error-reading tool, but a monitoring tool as well, allowing certain vehicle functions to be monitored. The nature and gamut of functions that can be monitored depend on the vehicle and the diagnostic tools used. Some manufacturers may even allow live control of certain aspects.

Common parameters that may be monitored in real time by an OBD2 scanner include:

  • Engine load as a percentage
  • Coolant temperature
  • Engine speed (RPM)
  • Voltage of the electrical system in Volts
  • Fuel consumption in real time
  • Currently selected transmission gear
  • Current vehicle speed and valid speed limits
  • Ambient temperature in Celsius or Faranheit

Notes on Error Storage

It is helpful to understand how error storage is performed, together with environmental data. These five factors are typically utilised by the control system when storing and handling stored errors. Thus, it is important to understand this when using an OBD2 scanner.

  1. Only reproducible errors are transferred to the error memory. If it is no longer confirmed during a subsequent driving cycle, the first entry is deleted from the memory.
  2. Information and errors relevant to exhaust emissions are always saved. They are allocated the highest priority.
  3. The check engine lamp will light up in the event of successive emissions-related errors.
  4. The Check Engine lamp will light up if there is damage or impaired operation of the catalytic converter.
  5. Exhaust-related errors are only automatically deleted from the error memory after 40 consecutive error-free journeys. For catalytic converter errors, the limit is 80 error-free journeys.

Types of OBD2 Scanners

The two main types of OBD2 scanners are those with an associated diagnostic reader, or those with a wireless connection to a smartphone and accompanying mobile app.

Standalone OBD2 Devices

Standalone devices are commercially utilized by workshops and you may have seen technicians using these. The error codes are displayed as-is and are understood by trained technicians, but normal people will not understand them and may need to check online. These devices may have their own battery or may utilize power from the OBD2 connector itself as their power draw is low.

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OBD2 Scanner with App

An OBD2 scanner with a mobile app is more popular among the enthusiast community, although workshops have recognized the increased functionality coupled with versatility that these offer. A Bluetooth or WiFi-enabled adapter plugs into the OBD2 port and establishes a connection to a smartphone where an app (eg: Carly) can be used to read and process the data.

The advantages of using this method are that mobile apps are very powerful, able to provide more details and background information. They can provide meanings and possible cause-relationship analysis of the error as well as the error code. Some apps will advise you if you still need to visit a workshop after checking the codes, or whether it is safe to proceed with your journey. An app such as Carly is the most extensive in terms of information displayed.

Utilizing the app method also makes it possible to feed the onboard computer with external data, such as in the case of tuning and coding.

How Much Does an OBD2 Scanner Cost?

It is difficult to place a flat rate on an OBD scanner. You can find devices for €50 or less, as well as devices north of €100, with very high-end devices around €5,000. There are several factors that influence the cost of an OBD2 scanner. These include:

  • Is it an integrated scanner/reader, or a mobile app-designed one?
  • Does it utilize Wi-Fi or Bluetooth for communication?
  • The potential reading ability — is it basic or comprehensive?
  • Does it allow two-way communication?
  • Does it only read errors, or offer comprehensive diagnostic functionality?
  • What is the speed of communication?
  • Can it be used for coding as well?

The average user might ask, why don’t I simply go to a workshop each time my “Check Engine” light comes on and get them to read it? Well, that can cost you a lot of time and money, as engine lights can pop up fairly frequently.

What Is the Advantage of a Fault Analysis with an OBD2 Scanner?

A workshop would charge between €30 and €50 for an error analysis, and that’s before any other costs are tacked on. In the long term, buying an OBD2 scanner is always more cost-effective as you can avoid unnecessary visits.

Here are some factors you should consider when purchasing one.

1. Quality

It’s better to purchase from established manufacturers, often at a higher price than to purchase a cheaper, no-name, or unknown brand device that can cause more problems in the long run. Remember to check out reviews online before making your decision.

2. Updates

Some device manufacturers regularly update their equipment with free software upgrades, others relegate them to obscurity after a certain time has passed, or charge for updates. Software updates are crucial in keeping the scanner up-to-date, especially for newer vehicles.

  What is an OBD Reader?

3. Car Manufacturer

Even though OBD2 is a universal standard, it can happen that a scanner is not compatible or doesn’t work well with your vehicle. So it’s best to check whether your chosen scanner is capable of reading your vehicle before committing to purchase. Ideally, you should not get a scanner that is tied down to one or a few vehicle brands, but one that can handle as many brands as possible.

4. Privacy

If a mobile app is involved, data privacy and data protection are prudent points to consider, as most apps save your customer data on a server for easy access and historical records. The best app providers provide precise information on collected data, how it is processed and if their servers are located in countries where GDPR (General Data Protection Regulation) applies.

5. Range of Functions

You should ensure that your chosen scanner is capable of reading all generic error codes, as well as outputting a comprehensive error diagnosis. Particular attention should be paid to additional functions, particularly vehicle-specific ones that pertain to your vehicle make and model.

We hope that you have a good overview of OBD and OBD2, scanners, readers, mobile apps, error codes, and the possibilities.

OBD2 Apps and Their Advantages

A few taps and presto, your smartphone can become a diagnostic tool for your vehicle, delving deep into the control units and uncovering errors without requiring a visit to a workshop. Apps like Carly, Pace, and RYD save you time and money! They don’t just diagnose small defects but provide detailed information on vehicle errors and whether it is safe to continue on your journey. Traditional OBD scanners with simple screens typically do not offer this much versatility.

OBD2 Apps, in a Nutshell

  • An OBD2 scanner connects to the car’s OBD2 port located in the driver area.
  • They connect to a mobile app on your smartphone via Bluetooth or Wi-Fi.
  • The app can read and interpret stored error codes.
  • It can also delete error codes once the fault has been rectified.

An OBD2 scanner is the mediator between your vehicle and your phone, acting as a liaison between the two, utilizing wireless technology such as Bluetooth or Wi-Fi.

Some systems require a scanner from the respective app manufacturer, as they are designed to work together. There are also universal apps that work with a wide variety of scanners but they can differ greatly and not offer the same level of reliability and versatility as a complete package. One example of a manufacturer who offers a finished solution that can utilize their app to provide diagnostics and even useful safety information is Carly, with the Carly app.

The Carly App

As a diagnostic device, Carly reads the error codes from the control unit and provides information on how to rectify them or if you should stop driving. You can even delete error codes.

For a fault diagnosis, the Carly scanner is connected to the OBD2 port in the car and then to your own smartphone (with the Carly app) via BLE (Bluetooth Low Energy). The Carly Scanner is suitable for both iOS and Android operating systems and supports many different vehicle brands, including BMW, Mini, Skoda, etc…

Note: Carly only works in conjunction with the Carly Scanner.

FAQs Carly Scanner for the Carly App

  • How much does it cost?
    • The scanner costs €59.90 and the app costs between €21 and €80, depending on the version.
  • What are the supported smartphone operating systems?
    • iOS and Android.
  • Which vehicle models and brands are covered by Carly?
    • Carly supports advanced functions for BMW, Seat, Skoda, Toyota, Volkswagen, Lexus, and Mini, and standard OBD functionality for most other brands.
  • Is there a return policy?
    • You can return the scanner within 14 days.

Here is an overview of the various functions of the Carly app:

Additional Carly Functions

In addition to diagnostics, the app allows various functions to be coded and some special functions to be activated. For example, with Carly you can code your lighting setting, which includes changing the brightness levels or even the indicator flashing intervals. Optical or acoustic signals on the vehicle can be set, as well as different warning signals, such as a seat belt reminder.

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Drivers of diesel vehicles will find the “DPF diagnosis” function very interesting. This allows the status of the diesel particulate filter to be read out and manual regeneration of the DPF to be initiated. Cars with gas engines have a similar function for the NOX catalytic converter. Depending on the vehicle model, the exhaust flaps can be controlled manually.

read error codes with obd2 adapter

Carly’s Used Car Check allows you to identify if a car has undergone mileage tampering. Vehicles store their mileage across various control units as well as the instrument cluster, and Carly can analyze the information and identify any manipulations.

With this app you also have the option of checking vehicle parameters while on the move, such as oil temperature, fuel pressure, etc.

The app’s “Digital Garage” also saves various vehicle data, the error history, maintenance intervals, etc. in an easy to read manner at all times.

The Carly App in a Nutshell

With the Carly app you can run deep diagnostics on your vehicle and the fault memory. The Carly app contains numerous features that are otherwise only implemented in professional-level devices. Some of these features include:.

  • Activation of hidden functions
  • Resetting maintenance intervals
  • Checking and manual regeneration of the diesel particulate filter
  • A similar function for NOX catalytic converters
  • Read out and deletion of error codes
  • Detection of speedometer manipulation (used car check)
  • Viewing engine parameters in real-time

Conclusion OBD2 scanner

We hope that our article has given you a comprehensive outline on the subject of OBD, history, scanners, readers, and mobile apps. Buying an OBD2 scanner makes sense, however, you should keep in mind your requirements, whether it is basic fault reading, or a more comprehensive analysis and real-time monitoring of vehicle parameters. So we recommend using an app such as Carly which comes with additional functions that would otherwise require extra charges from external parties and repair centers.