The On-Board Diagnostics II (OBD2) system is integral to modern vehicle diagnostics and monitoring. At the heart of this system lies the standardized 16-pin J1962 connector, providing access to a wealth of vehicle data. Understanding the Obd2 16 Pin Connector Diagram is crucial for mechanics, technicians, and car enthusiasts alike. This guide offers a detailed look into the pinout of this essential port, ensuring you have the knowledge to effectively interface with your vehicle’s diagnostic system.
The SAE J1962 standard defines the physical connector used for OBD2 communication in vehicles. This 16-pin connector, often referred to as the OBD2 port, is typically located within the passenger compartment of most cars and light trucks. While the physical connector is standardized, the function of each pin can vary slightly depending on the vehicle manufacturer and communication protocols used. However, several pins are consistently assigned across all OBD2 compliant vehicles.
Below are the standard pin assignments for the OBD2 J1962 connector, detailing the function of each of the 16 pins. Note that the connector comes in two types, Type A (12V) and Type B (24V), primarily differing in voltage supply for vehicle battery power at pin 16.
| Pin Number | Description |
|---|---|
| 1 | Manufacturer Discretionary |
| 2 | SAE J1850 Bus + (VPW / PWM) |
| 3 | Manufacturer Discretionary |
| 4 | Chassis Ground |
| 5 | Signal Ground |
| 6 | CAN High (ISO 15765-4 and SAE J2284) |
| 7 | ISO 9141-2 / ISO 14230-4 K Line |
| 8 | Manufacturer Discretionary |
| 9 | Manufacturer Discretionary |
| 10 | SAE J1850 Bus – (PWM-only) |
| 11 | Manufacturer Discretionary |
| 12 | Manufacturer Discretionary |
| 13 | Manufacturer Discretionary |
| 14 | CAN Low (ISO 15765-4 and SAE J2284) |
| 15 | ISO 9141-2 / ISO 14230-4 L Line (Optional) |
| 16 | Vehicle Battery Power: – Type “A” 12V/4A – Type “B” 24V/2A |
Key Pin Functions Explained:
- Pin 4 & 5 – Grounds: Pin 4 is the Chassis Ground, providing a ground connection to the vehicle’s chassis. Pin 5 is the Signal Ground, serving as the ground reference for the communication signals.
- Pin 6 & 14 – CAN Bus: These pins are crucial for vehicles utilizing the Controller Area Network (CAN) protocol, as defined by ISO 15765-4 and SAE J2284. Pin 6 is CAN High, and Pin 14 is CAN Low, forming the differential pair for CAN communication.
- Pin 7 & 15 – ISO 9141-2 / ISO 14230-4 (K & L Lines): These pins are used for communication based on ISO 9141-2 and ISO 14230-4 protocols, also known as K-Line and L-Line respectively. Pin 7 is the K-Line, used for diagnostic communication. Pin 15 is the optional L-Line, sometimes used for wake-up or secondary communication.
- Pin 16 – Vehicle Battery Power: This pin provides direct battery power to the diagnostic tool connected to the OBD2 port. It’s specified as 12V/4A for Type A connectors (common in passenger vehicles) and 24V/2A for Type B connectors (often found in heavy-duty vehicles).
- Pins 2 & 10 – SAE J1850 Bus: These pins are used for vehicles employing the SAE J1850 communication protocol, commonly found in older American vehicles. Pin 2 is J1850 Bus +, and Pin 10 is J1850 Bus -.
- Manufacturer Discretionary Pins: Pins 1, 3, 8, 9, 11, 12, and 13 are designated as manufacturer discretionary. Their functions can vary significantly between vehicle makes and models, and are often used for manufacturer-specific diagnostics or communication purposes.
Understanding this obd2 16 pin connector diagram is fundamental for anyone working with vehicle diagnostics, ECU programming, or performance tuning. By correctly identifying each pin’s function, you can ensure proper connection and communication with the vehicle’s onboard systems, facilitating accurate diagnostics and repairs. Always refer to vehicle-specific repair information for details on manufacturer-discretionary pin usage and ensure compatibility before connecting any diagnostic equipment.
