What is the OBD pin definition?
2 Answers
OBD interface pin definitions are as follows: 1. [1], [3], [8], [11], [12], [13] are manufacturer-defined. 2. [2] SAEJ1850 bus + [10] SAEJ1850 bus -. 3. [4] Chassis ground, [5] Signal ground. 4. [6] CAN-H, [14] CAN-L. 5. [7] K-Line, [15] L-Line. 6. [16] Constant power supply. Note: The definitions and functions of pins 1-16 can be understood as different software settings by various manufacturers, with each pin serving a different purpose. For example, pin 16 is only for power supply or detecting battery voltage and current.
Let me explain the OBD pin definitions - it's a fundamental automotive interface. The standard OBD-II diagnostic port is a 16-pin rectangular connector, typically located below the steering wheel. Pin 16 is the positive power supply connected to the battery, providing 12V power to diagnostic tools; pins 4 and 5 are ground connections, ensuring circuit safety. The critical data transmission pins are 6 and 14, used for CAN bus protocol to rapidly transfer engine trouble codes and real-time data like RPM; pin 7 sometimes uses K-line protocol, mainly for older vehicle diagnostics. Others like pins 2 or 10 handle J1850 protocol. Understanding these allows you to connect a scanner yourself to read engine light issues - just don't mix up the pin sequence or the tool won't work. I once helped a friend whose scanner showed gibberish because of reversed pins, and we had to check the diagram to fix it. Learning these basics can save money and hassle, preventing you from getting ripped off at repair shops.
