What is OBD2?

What Is OBD2?

OBD2 stands for On-Board Diagnostics version 2 — a system built into most modern vehicles that helps you understand what's going on under the bonnet. It’s what powers your Check Engine light and allows scan tools to read fault codes from your car’s computer.

Before OBD2 came along, car manufacturers used their own diagnostic systems. These varied wildly, making it harder to scan different makes. That earlier generation is often referred to as OBD1 — not a formal standard, just a catch-all for pre-OBD2 vehicles.

OBD1 vs OBD2 – What’s the Difference?

OBD1 (1981–1995):
Manufacturer-specific systems with different plugs and communication methods. There’s no universal tool or language — it’s a mixed bag.

OBD2 (1996+):
A unified standard introduced in the US to reduce emissions and streamline diagnostics. Vehicles must use a standardised 16-pin plug and be readable by a wide range of tools.

How Do I Know if My Car Is OBD2 Compliant?

Many people assume their vehicle is OBD2-compliant because of the plug or because online forums say so — but in NZ and Australia, compliance depends on where the car was sold new.

Here’s a general guideline based on our own testing and experience:

American Vehicles

• All models: 1996 onward

European Vehicles

• Petrol: 2001 onward

• Diesel: 2004 onward

Australian Vehicles

• Holden: From 2006 (Commodore VZ onward)

• Ford: From 2006 (Falcon BA onward, Ranger from 2007)

Japanese Imports (Common in NZ)

These vary — even by model and engine. But most are OBD2 compliant from 2008 onward. Here's a rough guide:

• Honda: From 2001

• Mazda: From 2001

• Toyota: From 2006 (Diesel: 2008)

• Subaru: From 2003 (Engine only), full OBD2 from 2008

• Nissan: From 2007

• Mitsubishi: From 2007

• Suzuki: From 2008

• Hyundai/Kia: From 2001–2006+

Important: Some earlier models may appear to have the correct plug (OBD2-style), but use a different protocol. VW, Audi, Nissan, and Toyota are common examples.

OBD2 in New Zealand & Australia

OBD2 became mandatory in NZ and Australia for new vehicles from 2006 onward. Before that, some vehicles included it, some didn’t — often depending on whether the manufacturer wanted to cut costs or steer repairs back to dealerships.

Many online resources — especially US-based ones — will tell you your car is OBD2 compliant when it’s not. Just because a 1998 Subaru in the US is OBD2 doesn’t mean the NZ version is.

If you're ever unsure, feel free to contact us — we've tested hundreds of vehicles locally and can usually tell you straight away.

What Does the OBD2 Port Look Like?

The OBD2 port is officially called the SAE J1962 connector. It’s a 16-pin trapezoid-shaped plug usually found under the dash near the driver's knees.

Just because a vehicle has this plug doesn’t guarantee OBD2 compatibility. Some pre-OBD2 cars use the same port but run a different protocol.

OBD2 Protocols Explained

Different manufacturers use different communication protocols within the OBD2 standard. Most scan tools support them all, but here’s a breakdown:

Other OBD2 Terms You Might See

• EOBD: The European term for OBD2

• JOBD: Japanese version of OBD2

• ADR 79/01 (ANZOBD): Australian/New Zealand legislation equivalent

They’re all versions of OBD2 — just under different names depending on where the vehicle was sold.

What Are OBD2 Codes?

When your car detects a fault, it stores a Diagnostic Trouble Code (DTC). These codes can be read using any OBD2 scan tool.

Need to look one up? See our list of OBD2 codes here.