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OBD1 vs. OBD2: Definite Interpretation and Comparison

OBD1 vs. OBD2
OBD1 vs. OBD2
Credit: OBD Focus.

OBD, a built-in computer system in modern vehicles that checks on malfunctions, is an essential part of our cars. However, OBD1 and OBD2 systems may get you confused. Do you know the difference between both or the pros and cons of OBD1 vs. OBD2?

If not, don’t worry – you’re not alone. In this article, we will explore what an OBD is, compare OBD1 vs. OBD2, and tell you how to check what OBD car you have.

OBD1 vs. OBD2, OBD vs. OBD2: The Basis

To start with, let’s identify the differences between all the OBD systems modern vehicles come with.

OBD: What is it?

‘On-Board Diagnostics’ or OBD is a computer system in your car. Introduced in the 1980s, the system basically checks your cars engine performance for any malfunction. It is made up of an Electronic Control Unit (ECU) that uses various sensors to detect problems.

For instance, problems such as:

  • Inconsistencies with the fuel mixture
  • Issues with the car’s catalytic converter
  • Problems with your spark plug, etc.

To figure out the problem you’re having, you need to check your car with OBD scanning tools. These scanning tools are different for OBD1 and OBD2, which are more standardized versions of the first generation OBD system.

Here is a play by play on OBD1 vs. OBD2 comparison.

OBD1: California Standard

On the whole, the original OBD only turned on the ‘check engine’ light in cars. The OBD1 system came out in the early 1990s when automakers began pushing for standardized OBD systems.

Consequently, the California Air Resources Board (CARB) required all cars to have some form of OBD1 in 1991. Despite being a California Standard, OBD1 systems were found in vehicles nationwide until the standardizing of OBD2.

What is OBD1?

The OBD1 gave cars a system that detected problems and then reported them as trouble codes. Furthermore, these early systems were made of proprietary connectors, protocols, and hardware interfaces.

Therefore, to diagnose problems, a mechanic would have to use a different tool for different cars. This was because OBD1 was not standardized amongst automakers.

OBD1 Years

The California Standard OBD1 system was in use across America from 1991 to 1995. After that, CARB standardized a newer system termed OBD2.

OBD2: Federal Universal Standard

The OBD2 became the official Federal Universal Standard in 1996. In simple words, it was a more advanced version of OBD1.

What is OBD2?

OBDII Connector Shape
OBD2 Connector Explained

Credit: csselectronics.com

OBD2 systems are like OBD1 except they perform more enhanced diagnostic functions. Additionally, unlike OBD1s, they require a standardized exchange of digital data between ECUs and scanning tools. OBD2 vehicles only need one universal adapter to communicate via the OBD2 protocols.

What Year did OBD2 Start?

The first OBD2 model was introduced in 1994. Afterward, it became commercial in 1996 and has been in use ever since. This means you can easily use the same scanner you use for a car you bought this year for a car manufactured in 1996. 

OBD1 to OBD2: Excellent Development of Car Technology

Furthermore, the move from OBD1 to OBD2 was significant for the automotive industry. The OBD1 was becoming increasingly unpopular. In short, it was causing a lot of issues for car owners as well as professional mechanics. However, with OBD2, running diagnostics gets much easier.

Why was OBD1 Developed to OBD2?

The main issue with the OBD1 was that it wasn’t standardized across car manufacturers. Hence, diagnosing engine problems became difficult. Trouble codes were different for different cars.

For example, a Ford and a Toyota with the same engine problem would show different codes. It caused CARB to mandate regulations on standard OBDs in 1994

To solve the problem, the OBD2 came out in 1996. It’s been the nationwide standard ever since. The OBD2 allows cars to support the same type of scanner. Additionally, trouble codes are now universal as well. Although, automakers do add specifications from time to time.

For its effectiveness, OBD2 is now the most commonly used car system in the US. With advances in car technology, manufacturers have made more and more advancements to OBD2 systems in the last few years.

You can now use an OBD2 scanner to connect with your car’s computer, view immediate diagnoses, and can do much more.

Difference Between OBD1 and OBD2: Complete Comparison Chart

StandardCaliforniaFederal Universal
Years in Use1991 to 19951996 till present
Interface TypeManufacturer specificUniversal

OBD2 vs. OBD1: Key Differences Explained

As mentioned above, the OBD1 is a California Standard system that was used from 1991 to 1995. In contrast, the OBD2 is a Federal Universal system that is still in use today.

Further differences are divided as follows:

Interface Type:

Since OBD2 is standardized for all US vehicles, a single scanner can support all manufacturers. In contrast, an OBD1 interface connection depends on the type of manufacturer. This means a different OBD1 scanner for different cars.


Furthermore, OBD1 requires a corded connection with the vehicle’s console whereas OBD2 can be connected wirelessly through either Bluetooth or Wifi. Although, corded options exist for OBD2 as well. 


Also, OBD2 has a higher accuracy than OBD1. OBD2 can display messages specifying the type of code. OBD1, in contrast, can only display CEL messages without any code details. Additionally, OBD2 performs a broader range of functions.

For example, these include the monitoring of:

  • Fuel Control
  • Climate Control
  • Catalyst Accuracy
  • Heating Circuits


OBD2 systems are more reliable. They will alert you about even minor problems. The advanced system performs multiple diagnostic tests at the same time to test your engine performance. On the other hand, OBD1s require a component to completely fail for the ‘check engine’ light to come on. 

Is My Car OBD1 or OBD2?

After all this, you might be confused. What type of OBD is your car? A straightforward way to tell is to check the year your vehicle was manufactured. If it’s older than 1996, chances are it is OBD1. If it’s made after 1996, it’s definitely an OBD2. However, certain automakers began using OBD2 in 1995. Find out if that’s the case with you.

You can do this by checking your car’s interface system. OBD1 interface systems differ from car to car, manufacturer to manufacturer. OBD2 is generic. The standard interface for OBD2 is a 16-pin connector. If your car has that, then it’s undoubtedly an OBD2.

Another place you can check for your car’s OBD system is under the hood. If you look under the hood, there should be a label. This will state whether your car’s certification is OBD1 or OBD2. The owner’s manual will also be able to tell you this. 

Should I Take an OBD1 or OBD2 Scanner for My Car?

Additionally, having a scanner on hand can be really useful. Scanners can allow you to do minor fixes yourself, saving you money and time. Moreover, a scanner will let you determine the damage and make an informed decision with the mechanic.

OBD2 Scanner
OBDII Scanner
OBD2 Scanners.
Credit: youtube.com

If your car was manufactured after 1996, then definitely go for an OBD2 scanner. OBD2 scanners are affordable and accessible to connect to your vehicle. In contrast, OBD1 scanners tend to be unnecessary most of the time. You only need one if you’re having trouble doing a maintenance job on an older car.

In that case, it will be annoying trying to find the manufacturer specific scanner and trouble codes. However, having the specified scanner is ideal if you do have an OBD1 car. While not all OBD1 scanners are readily available, you can look for one online or in local car parts stores. 


We hope the differences between OBD1 and OBD2 explained in this article aren’t hard to understand. They both have their uses. However, OBD2 is the clear winner of the two and more advanced. It’s just easier for a car owner to have a modern system in this technological day and age.

Simple Introduction to OBD2.
Credit: youtube.

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