Obd2 Diagnosis


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TOAD is the ultimate tool to read, diagnose obd2 codes and reprogram ECUs. Designed specifically to allow you to dive extremely deep into your car’s engine electronics to modify performance, analyze data and diagnose all systems, this is our favorite engine-specific OBD2 software, period.

A must-have in any shop and for any serious car guy

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OBD (On-Board Diagnostic System)

OBD is the general system that makes it possible for a car’s computer to be interactive. As the software in the car’s computer has become more and more user-friendly, the OBD has become more of a relevancy to not just car manufacturers, but the car owners themselves. OBD is a technique that helps to diagnose problems and adjust settings within a car’s computer system.

OBD is not a new concept, however, it has been around for decades, and was invented to satisfy two concerns with cars primarily. Firstly, the car needed a way to regulate its emissions system. Secondly, as electronic fuel injection took off in the 1980s, they needed a way for the car to record fuel electronically, which is what the OBD is also known for doing.

What is On-Board Diagnostic System Data Used For?

OBD is the reason why fleet solutions and telematics are possible. Without OBD systems, there would be no simple way for car owners and specialists to receive data from a specific car. With all the different protocols of OBD, not all systems are compatible with every vehicle on the road today. Decent telematics systems should be able to understand diagnostic codes for most consumer vehicles as well as diesel vehicles.

With OBD systems, the following tasks can be achieved:

  • Analyze wear trends to determine how fast specific car parts are aging.
  • Diagnose vehicle troubles instantly, the moment they happen.
  • Measure the performance and behavior of the vehicle being driven.
  • And much more.

History of OBD Diagnosis

Before the creation of OBD, problems were brought to one’s attention by a couple of gauges, either on the car’s dashboard or somewhere under the hood. Car owners and mechanics also had to notice problems themselves by checking for unusual smells, strange sounds, and other strange happenings coming from the car.

As the car had been slowly evolving over time, where it became much more complex compared to 40 years ago, computers and other instruments have been added to cars in order to deliver better performance. Video display terminals were introduced in the 1960s, along with temperature gauges, oil instruments and vacuums; all of which were used to help detect problems from inside the car.

The Birth of OBD

In 1968, however, the OBD computer system was brought out of the concept phase and into the automobile, with Volkswagen being the first to create it. This system had scanning capabilities that oversaw all the bells and whistles going on inside the car’s engine and other inner workings. In 1978, Datsun created a simplified version of the OBD system that contained restricted set of non-standardized features.

In 1980, General Motors also made improvements to OBD with the ALDL, or assembly line diagnostic link. This system is able to translate a problem into a code that the car owner could see. This code would show exactly what was wrong with the car just by referring to the car’s manual.

The Evolution of OBD

Over time, though, human have been phased out in the car diagnostic process, and soon replaced with computers that are not known to make mistakes. With more recent iterations of OBD, sensors are connected to many different parts of the car, such as the cooling system, the engine and more, all connecting to a device known as the terminal block located on the car’s exterior.

Also in more recent cars, drivers should be able to know if there is a problem right from their seat, as a light in the form of a symbol or an indicator would turn on that would display a message. These symbols represent different warnings that have unique pictures. For example, seeing a picture of a car battery light up would indicate that the car’s battery is low. There are various other symbols for problems like brakes, tire pressure, engine, oil, washer fluid, gas and more. If a user does not know what any of the symbols that appear mean, he or she can always refer to his or her car’s manual. This is a staple in cars that we still have to this day, on account of how useful and helpful they have become, allowing car owners to take the right course of action for how to handle the problem that the car has.


OBD Timeline

ob timeline

The Standardization of OBD

OBD and similar computer systems in cars were not only popular over time, but more of a requirement for car manufacturers.

Cars have been known to be highly pollutant machines within the first several decades of their inception. As a means to mitigate this pollution, Congress passed the Clean Air Act in the late 1960s, the inspiration for the founding of the EPA, or Environmental Protection Agency. The EPA over time set standards for car emissions created by manufacturers. For instance, all cars made in 1975 or later required a catalytic converter, a device used to mitigate the range and effects of toxic gasses and pollutants. To help manufacturers control these emissions for their automobiles, computers systems such as OBD or similar were installed into newer cars. Car makers also included ignition and electronic fuel injection systems into their vehicles, which are utilities to help car owners preserve fuel, while also keeping emissions to a minimum.


Diagnostics are the backbone of OBD systems. When the sensors inside of a car detect an abnormality in the car’s inner workings, they relay a message to the person in the driver’s seat known as a “warning sign” or “trouble code”, which can come in the form of a lit up signal on the dashboard, such as a picture of an engine or battery. The scanners in OBD systems can verify certain codes to properly understand what the problem with the car is. Once the problem is fixed, the light no longer stays on, and the problem is wiped from the car’s memory.

The car’s memory records the problem via a code that consists of one letter and three or four numbers. These codes typically start with either B, C, P or U. B stands for body, C stands for chassis, P stands for powertrain, which involves both the engine and the gearbox, and U stands for user network.

The first letter in the code will either be a 0 or 1. 0 means that it is a generic fault or a human error. 1 means that it is a problem where the manufacturer is at fault.

The second letter in the code can range from 0 to 8 or 9, all representing a certain area within the body, chassis, powertrain or user network. For the powertrain, for instance, a 1 could mean a problem with the fuel or air, 2 could mean a problem with the ignition system, 3 could mean a problem with the transmission and so on and so forth.

The third and other letters can indicate specific problems with a certain part. These are not ranged from 00 to 99 or 999, but a car owner can memorize a distinct code that other users might have experienced before.

What Is An OBD Adapter?

One can buy an OBD adapter that is sold separately from a person’s car. ODB adapters work on any kind of care that is made after 1996. They come in wireless forms, without any messy cables or connections, and cost as much as 20 dollars. There are more expensive adapters for sale that come with additional features, but there is still plenty that one person can do with a cheaper adapter.

OBD adapters today are compatible with smart device apps such as Torque, HobDrive, Carista OBD2 and OBD Car Doctor Pro for Android and Engine Link, EOBD Facile and OBD Auto Doctor for iOS. More expensive OBD adapters come with 3G and GPS compatibility, power saving features, and apps that their own brands develop.

There are also a series of standalone handheld tools that are available to car owners in the form of scanners and other diagnostic tools. These companies that make these products include Kobra Wireless, Bluedriver, OxGord, Autel, Actron, FIXD, Innova and Topdon.

OBD Software In Computers And Devices

Many cars come with an OBD 2 ports that gives access to data sourced from the engine control unit. In order to have the information available to you in an easy to decipher manner, you will need an external device that can translate this data for you.

An OSB scanner is used to receive data code and other important information about the status of the car. An ODB scanner can connect to a computer, but basic car repair knowledge is also recommended.

ODB software generally comes in two components: The computer application software itself and the device that connects to the car’s onboard motherboard. The software analyzes many factors about the car as well as its performance as it drives from point A to point B. The software can inform the driver about what they can do to optimize the car’s health, such as drive more carefully and reduce the consumption of fuel.

These are the six most popular ODB scanner software programs for the following platforms

Windows computers:

  • AutoEnginuity’s ScanTool
  • ProScan
  • PCMScan
  • EOBD Facile
  • OBD Auto Doctor
  • Movi and Movi Pro
  • For Android devices:
  • Torque Pro (OBD 2 & Car)
  • HobDrive
  • OBD Car Doctor Pro
  • Carista OBD2

For iPhone:

  • OBD Auto Doctor
  • EOBD Facile
  • Engine Link

OBD standalone tools:

  • KOBRA Wireless OBD2 Car Code Scan Tool
  • Topdon TD309 Diagnostic Scan Tool
  • INNOVA 3030g Diagnostic Code Reader
  • FIXD
  • Actron CP9679 OBD2 AutoScanner
  • BlueDriver Bluetooth Professional OBDII Scan Tool
  • Autel Maxidas DS808 Automotive Diagnostic Tool
  • OxGord OBD2 Scanner Tool
  • Autel MaxiScan MS309 Diagnostic Code Reader
  • Launch CReader 3001 OBD2 Scanner
Useful Tasks With OBD Adapters

With an OBD adapter, one can do things like diagnose a check engine light. The check engine light can mean that one one of many different things are wrong with the car. Unless a car owner owns an OBD adapter, the only way to determine what is wrong with the car is by taking it to a mechanic. The aforementioned apps can all show a person an error code to help them determine a specific problem with the car, allowing the car owner to explore his or her options for how a car owner could fix it with or without outside assistance. The problems that a car owner could encounter can range from severe to investing just a few minutes to take care of on one’s own.

One can also see how much a drive will cost in gas. A typical car owner likely know how much money he or she has to pay for gas until his or her tank is full, but how much will it cost to just take the care to work or across town? An app with an OBD adapter makes it possible to see how much gas is expanded, leading to how much money it costs for the car to go from point A to point B each time. This is a great feature to help car owners potentially manage fuel and/or money.

A OBD adapter owner can also easily pinpoint where his or her car had been parked. Whether you are Christmas shopping, parking somewhere in the city for a concert or sports game, or out in the wilderness, the app that a person has can use the phone’s map to show you where your car is parked. For more premium OBD adapters, a person can even track the whereabouts of the car without it having to be close to your phone. In the events of a family member borrowing the car or the car getting stolen, having a way to track it would be very useful.

Premium OBD adapters also can help in emergency situations, such as in a collision. OBD adapters will know when a car has been in a crash, and before you know it, the driver or owner will have an operator call him or her and ask if he or she needs assistance. If the person on the other line were to answer yes, or wouldn’t be able to answer the phone, emergency services will be summoned to the location of the the collision. If the user responds, the operator will stay on the line with him or her until the help arrives.

a. OBD And Smart Home Devices

You can also connect an OBD adapter with a smart home gadget, like Alexa or IFTTT. Alexa for instance can record any error codes and other problems that the OBD scanner might pick up, and wherefore will tell you what problems that the car may be having on the car’s behalf. Alexa and other smart home devices can also remind OBD adapter owners of when to buy more gas and to get their oil changed, among other things.

b. OBD In Race Cars

But that isn’t all. While diagnostics are the most important part of OBD systems, but they can also make an owner’s car move faster. Multiple aftermarket brands offer utilities for OBD systems that can not just monitor aspect of an owner’s car such as fuel economy, but they can also monitor performance stats such as power output. Race car drivers use these enhancements to their OBD systems to see how their performance is on the race trace, and regular car owners are slowly catching on to this trend.

Some businesses also sell performance upgrades for certain vehicles that modify or reconfigure software to enable more horsepower in the car. Because newer cars today rely so much on computer setting, changes in software can be as useful as installing a brand new car part. One thing to keep in mind, though, and that is while these upgrades are meant to push the car’s limits, other limits are made in place, such as less fuel or stability. These upgrades also may void the warranty of an owner’s car, so anyone should only do so at one’s own risk.

c. OBD And Insurance

Even insurance companies have their own OBD adapters, as their customers connect then to their cars as a means to obtain discounts. Adapters, such as ones issued by Progressive or Allstate, can record how fast a driver speeds, brakes, how long a person drives and how often they drive. If they meet certain criteria and do not go outside the limits of the road rules, such as driving too fast. The insurance company will know he or she is a good driver, and thus will be awarded with savings. If a driver drives too recklessly, it only makes sense that no rewards are issued until the driver practices good and consistent driving for a period of time.

But with that said, there is so much that this system from the mid 1990s can do. There is just so much a person can buy to make his or her OBD system more engaging and useful throughout the life of the car.



OBD 1 is the diagnostic system that analyze emissions from a car’s exhaust. It gives a warning sign or indication in some form to see how the car overall is working.

LEARN MORE About obd 1

When a warning light does turn on, car owners and technicians are quick to find out exactly what the problem is with the car, and from there, the necessary steps can be taken by the owner or technician to help solve the corresponding problem. For instance, a picture of a windshield with a trail of water spraying out of it indicates that the car has low washer fluid.

OBD 1 was the first type of OBD system used in the United States. First being mandatory in California, other states soon after adopted this type of system. The main draw to OBD 1 was the ability to prolong the life of the car overall, thanks to the useful warning signs and the inclusion of the catalytic converter. The reign of OBD 1 was short-lived, however, with other forms of OBD soon replacing it in the 2000s. Few older cars with OBD 1 systems are still on American roads today.

OBD 1 is known as a manufacturer-specific system, meaning that only car manufacturing experts would be able to read and understand it.

MOBD, or Multiplex OBD is a variant of OBD 1 utilized by Toyota, used before the inception of OBD 2. MOBD promised more secure connections between the system and the parts inside the car, but was also a short-lived idea due to the processing capabilities of the car overall.


About obd2

Even though the OBD 1 system was ahead of its time, there wasn’t a whole lot of support for it in the automobile industry, but there still was a need for a system that was improved and more accurate from OBD 1. OBD 2 was introduced as a significant upgrade from OBD 1, and it known as the standard system for car manufacturers in many different countries, including America. OBD 1 was not even six years old before OBD 2 became available. Every car maker that sold vehicles in America all sold cars containing OBD 2 starting in 1996. It is known to be a smarter and more stable system compared to its older version, making it much easier to utilize for any car owner or specialist.

As mentioned previously, OBD 2 is used in most cars available today, as it is a more in-depth system for car owners in the case of a problem with the car. It can give better details of what sort of problems the car may have than OBD 1, such as unique codes to indicate a problem with a certain car part. This helps to show car owners and specialists to more specific problems that can better help them decide on what they need to do to fix the car.

OBD 2 And GPS Tracking

OBD 2 can allow GPS fleet tracking devices to quietly obtain information from the car such as specs on the engine, fuel usage, fault codes and more. This information is sent to a software interface, allowing fleet managers to observe the performance of the vehicle.

Comparisons Between OBD 1 And OBD 2

When OBD 1 was created, its primary goal was to create the diagnostics system that concentrated on emission controls from inside of a vehicle. However, despite the potential that the system had, it was not all that beneficial to many car manufacturers.

With OBD 2, as mentioned previously, it really is a big step up from OBD 1 in just a five-year difference. The messaging and signaling abilities of OBD 2 made it a better system overall, and had more unique responses that could be notified to car owners and specialists. OBD 2 is generally better to determine what type of problem a car owner might be facing with an engine.

Furthermore, OBD 1 is generally connected to the console, whereas OBD 2 uses ports without connects and via remote devices. Data is read with a tried and true Bluetooth connection in newer cars, so that makes it much simpler to diagnose a problem with a certain car

CriteriaOBD 1OBD 2
Years Used1991-19951996-present
NatureCalifornia StandardFederal Standard
InterfaceManufacturer specificUniversal interface
FunctionRetrieve diagnostic information and inform drivers of engine problemsRetrieve diagnostic information and inform drivers of engine problems
BenefitTotal energy and fuel consumed by the vehicle and then output which comes outTakes into account different calculations and codes to solve the problems that are faced
ApplicationWas not able to gain much popularityWas implemented from the beginning because of the options available
Location Of OBD 2 In Cars

The OBD 2 port is to be found underneath the dashboard on the driver’s side of thevehicle. The port will have either a 6-pin, 9-pin or 16-pin configuration. The OBD 2 system is capable of displaying data code for problems from parts such as the powertrain, emission controls and more. You can also get information about your specific vehicle, like how many time the car turned on, as well as the VIN and CIN (calibration identification number) of the car.




European On-Board Diagnostics system, or EOBD, is the standard system adopted by Europe.


At the turn of the century, January 2001, all petrol cars are required to be built with EOBD emissions. For diesel cars, this rule came into effect in 2003. Like the ETA, the European Union also made this a law for car manufacturers as a way to reduce emissions from each car being made and used.

There are some comparisons to be had with EOBD and OBD 2, but they are not one in the same by any means. There are OBD 2 systems that work only with newer petrol cars sold in Europe, and that is not the case with all British and European cars from 1996. There are also differences in certain parts, in addition to how they are named. For instance, the trunk is actually known as the “boot” in British English.


Despite how this system is named, EOBD 2 is not a newer version of EOBD. While EOBD stands for European On-Board Diagnostics, EOBD 2 stands for something dramatically different, which is “Enhanced On-Board Diagnostics, 2nd Generation”.

LEARN MORE About Eobd 2

EOBD 2 generally refers to features on OBD 2 and EOBD systems that are exclusive to a certain manufacturer. These features are meant to reach certain parameters and more detailed information about the car in question, which could be more beneficial than just a standalone EOBD or OBD 2 system. EOBD 2 features are not available for sale or resale, and they are only available when purchasing a car of a certain make, like Nissan or Volkswagen. Despite this, there are no such cars that require EOBD2 systems, and cars with said systems can function without the extra features from said manufacturers.




World Wide Harmonized On-Board Diagnostics (WWH-OBD) is a global system that most parts of the world use for vehicle diagnostics. Implemented by the United Nations, these systems monitor various aspects of a vehicle including emissions outputs and engine fault codes. This type of ODB system is known as one that is future-proof. Unlike OBD 2 systems, WWH-OBD systems can allow for expansions and upgrades in data. In other terms, WWH-OBD expands on the current foundation of OBD 2 and provides the user with much more diagnostic information.

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