Understanding your vehicle’s On-Board Diagnostics II (OBD2) system is crucial for modern car maintenance and diagnostics. The OBD2 connector is the gateway to this system, allowing mechanics and car owners to access a wealth of information about their vehicle’s health and performance. A common question that arises when dealing with OBD2 systems is: How Many Pins Obd2 connectors actually have?
The OBD2 connector is designed with 16 pins. This standardized 16-pin Diagnostic Link Connector (DLC) is a universal interface mandated in most cars and light trucks manufactured after 1996 in the United States, and later in other parts of the world. While there are 16 physical pin locations, it’s important to note that not all of these pins are always populated or active in every vehicle. The specific pins that are used depend on the communication protocol that the vehicle employs.
The location of the OBD2 connector is typically within easy reach from the driver’s seat, usually under the dashboard. For vehicles sold outside of the US, especially in international markets, checking the OBD2 connector pin configuration can be helpful to ensure compatibility with scan tools and diagnostic equipment. While an emissions sticker under the hood might indicate OBD II, EOBD, or EOBD2 compliance, examining the pin layout provides a more direct confirmation of the communication protocols supported by your vehicle. It’s worth noting that even if the pinouts appear to match a specific protocol, there might still be slight variations in international vehicles that could affect functionality with certain scan tools.
For vehicles sold within the US, OBD2 compliance is mandatory, simplifying the process. However, understanding the pin configuration becomes relevant when you need to determine if your vehicle uses a specific protocol, such as the Controller Area Network (CAN) protocol, which is common in newer vehicles.
The Auterra Dyno-Scan product, for example, supports up to 5 different OBD2 protocols. Each of these protocols utilizes a distinct set of pins within the 16-pin connector to establish communication between the vehicle’s computer and external scan tools. Some pins are essential for every protocol, while others are optional depending on the specific vehicle’s communication system. It’s also possible to find additional pins populated in the connector that are not relevant to the standard OBD2 communication protocols.
To understand which protocol your vehicle uses, and consequently which pins are active, you can examine the OBD2 connector. Below is a front view diagram of a standard vehicle OBD2 connector, followed by pinout details for the most common OBD2 protocols: CAN, ISO/KWP, VPW, and PWM.
Vehicle OBD II Connector (front view)
(Diagram of OBD2 Connector Pin Numbering – Image from original article would be inserted here)
CAN Protocol Pins
If you observe that pins 5, 6, 14, and 16 are populated in your OBD2 connector, it indicates that your vehicle likely supports the CAN protocol. CAN (Controller Area Network) is a more modern and widely used protocol, especially in newer vehicles.
| Pin # | Description |
|---|---|
| 5 | Ground |
| 6 | CAN High (Data) |
| 14 | CAN Low (Data) |
| 16 | Battery Power |
ISO and KWP Protocol Pins
If pins 5, 7, 16, and optionally 15 are populated, your vehicle is likely using ISO (International Organization for Standardization) 9141-2 or KWP (Keyword Protocol) 2000 protocols. These are older protocols but still found in many vehicles. Pin 15 is optional and might not always be present.
| Pin # | Description |
|---|---|
| 5 | Ground |
| 7 | K-Line (ISO 9141-2 & KWP2000 Data) |
| 15 | L-Line (ISO 9141-2 & KWP2000 Data) – Optional |
| 16 | Battery Power |
VPW Protocol Pins
Vehicles using Variable Pulse Width Modulation (VPW) protocol will typically have pins 2, 5, and 16 populated in their OBD2 connector. VPW was commonly used in General Motors vehicles.
| Pin # | Description |
|---|---|
| 2 | J1850 Line (VPW Data) |
| 5 | Ground |
| 16 | Battery Power |
PWM Protocol Pins
Pulse Width Modulation (PWM) protocol, primarily used in Ford vehicles, is indicated by populated pins 2, 5, 10, and 16.
| Pin # | Description |
|---|---|
| 2 | J1850 Line (PWM Data) |
| 5 | Ground |
| 10 | J1850 Line (PWM Data) |
| 16 | Battery Power |
In conclusion, while all OBD2 connectors have 16 pins, the active pins and their configuration are what determine the communication protocol used by your vehicle. Understanding these pinouts is essential for diagnosing vehicle issues and ensuring compatibility with OBD2 scan tools and diagnostic equipment. By checking the populated pins in your OBD2 connector, you can gain valuable insights into your vehicle’s diagnostic system and communication protocols.
