What is the pinout definition of the OBD diagnostic interface?

1 Answers
LaBrielle
07/29/25 11:12pm
The automotive OBD diagnostic interface has a total of 16 pins, each representing different definitions. Generally, pin 2 is the bus positive, pin 4 is chassis ground, pin 5 is signal ground, pin 7 is the K-line, pin 10 is the bus negative, pin 15 is the L-line, and pin 16 is only for power supply or detecting battery voltage and current. The remaining pins are assigned functions by the manufacturer. The following is an introduction to automotive OBD: 1. The automotive instrument OBD is the On-Board Diagnostics system. 2. It allows maintenance personnel to read driving information and vehicle fault information fed back by the engine and other controllers. 3. OBD can store vehicle fault information. When we repair a vehicle and the fault light comes on, maintenance personnel will connect a data transmission cable to the OBD interface to quickly determine the fault and proceed with repairs. 4. It records vehicle driving information, such as engine conditions, oil temperature, water temperature, etc., allowing us to understand the vehicle's status at any time, thereby ensuring greater safety for the vehicle.
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