OBD connector: Everything you need to know
The OBD connector is a key component in modern vehicles when it comes to diagnostics and maintenance. Whether reading error logs, detecting engine problems, or resetting service intervals – the OBD connector enables fast communication between the vehicle and the diagnostic device. In this blog, we answer the most important questions about the OBD connector, from its legal requirement to selecting the right connector for your vehicle.
Is an OBD connector mandatory in every new vehicle?
Yes. Since January 1, 2001 (gasoline) and January 1, 2004 (diesel), the OBD2 connector has been legally required for all newly registered cars in the EU. This is based on EU Directive 98/69/EC , which makes on-board diagnostics (OBD) standard.
This means that every new vehicle registered after these deadlines must be equipped with an OBD2 interface. Without this connector, a vehicle may no longer be marketed in the EU.
Which OBD connector do I have?
Basically there are OBD1 and OBD2 .
- OBD1 : In vehicles before approximately 2001 (gasoline) and 2004 (diesel). There was no standardized format for this connector. Each manufacturer used its own connectors and protocols.
- OBD2 : Standard since the above-mentioned dates. Almost all current vehicles have this connector.
To find out exactly which connector you have, take a look at your vehicle's manual or under the dashboard . Vehicles built from 2001/2004 onwards usually have the standardized 16-pin OBD2 connector.
Are all OBD connectors the same?
Not quite. While OBD2 is standardized, there are different protocols , such as ISO 9141, CAN, KWP2000, or SAE J1850.
That means:
- The shape of the connector (16-pin) is the same.
- Internal communication may vary.
Modern diagnostic tools usually automatically detect the correct protocol. However, for older vehicles, it may be helpful to familiarize yourself with the exact protocol beforehand.
Which OBD connector does my car have?
All cars from 2001/2004 onwards almost always have the OBD2 standard .
You can check the exact execution in several ways:
- Onboard manual : There is often a reference to OBD2 there.
- Sticker in the engine compartment : Some manufacturers indicate the standard there.
- Practical test : Connect a modern OBD2 diagnostic device – if it communicates immediately, it is OBD2.
For vintage cars or vehicles from the 1990s, however, there may still be OBD1 or even manufacturer-specific connectors.
Are OBD connectors legal?
Yes. OBD connectors are completely legal . The interface is primarily used for emissions monitoring and is therefore mandatory.
Reading error codes, sensor values or maintenance intervals is legal.
Restrictions only apply if you use an OBD device to manipulate engine controls , for example to increase performance without registration – in this case, traffic law applies.
Are all OBD2 connectors the same?
Yes, as far as the design is concerned.
All OBD2 connectors have the same 16-pin socket and are compatible with all OBD2-capable vehicles. The only differences are in the software and supported protocols.
A high-quality diagnostic device can automatically detect and process these differences.
What is the best OBD connector?
It depends on the application:
- For hobby mechanics : We recommend compact Bluetooth or WLAN adapters such as the Vident iLink400 or OBDLink MX+, which connect to the smartphone.
- For workshops : Professional diagnostic devices such as Panasonic CF-D1 with VAS6154B or Autel MaxiCOM offer deeper diagnostic options and manufacturer-specific adaptations.
Regular software updates are important to support new vehicle models and protocols.
What does the OBD connector do?
The OBD connector is the vehicle's diagnostic interface . It connects the car's control unit to a diagnostic tool or laptop.
Features:
- Read and delete error codes
- Check sensor values (e.g. lambda sensor, air mass meter)
- Monitor exhaust emissions
- Reset service intervals
- Carry out coding and adjustments (for professional devices)
In short: the entire vehicle condition can be analyzed via the OBD connector.
How many pins does an OBD connector have?
An OBD2 connector has 16 pins .
Not every pin is used in every vehicle, but they all use the same layout. Some important pins:
- Pin 4 & 5 : Ground
- Pin 6 & 14 : CAN bus (communication)
- Pin 16 : +12 V on-board voltage
Depending on the vehicle and manufacturer, additional pins are used for additional functions.
Where is the OBD connector on BMW?
In BMW, the OBD2 interface is usually located in the footwell on the driver's side , under the dashboard near the steering column.
In some models it may be hidden behind a small cover or flap.
Tip: Look for a rectangular connector with 16 contacts – often near the fuses.
OBD connectors are essential for diagnostics and maintenance
The OBD connector is now standard in every modern car , making vehicle diagnostics easier than ever. Whether for private hobbyists or professional workshops, with the right OBD2 device, errors can be quickly identified and resolved.
Those who value quality benefit from reliable data, long-term software updates, and ease of use.