What is the voltage of the LIN bus line?
2 Answers
The voltage of the LIN bus is 12V. The control units controlled by the LIN bus are generally distributed in close proximity to each other. Data transmission is single-wire, with the longest data line reaching up to 40m. The master node is configured with a 1kΩ resistor terminating to the 12V power supply, while the slave node is configured with a 30kΩ resistor terminating to the 12V power supply. Currently, the alliance is actively working to promote the LIN bus to achieve ISO international standards. The LIN bus conformance test specification is uniformly issued and managed by the LIN Alliance, and only core members of the LIN Alliance have access to it. This specification aims to unify the quality and performance of various LIN module nodes, ensuring the normal operation and safety of the entire vehicle after connecting to the LIN network. Therefore, OEMs in Europe and America require that the components provided by their suppliers must pass the certification report from a testing agency certified by the LIN Alliance.
As a driver with over a decade of experience, I often encounter LIN bus-related issues. Under normal circumstances, the LIN bus voltage typically fluctuates around 12 volts, varying between approximately 9 to 18 volts depending on the vehicle's electrical system status. The LIN bus is part of the vehicle's low-speed communication network, used to control functions like window operation and seat memory. If the voltage drops below 9 volts, signal transmission becomes unstable, potentially causing sudden window operation failures or increased minor malfunctions. I personally experienced lighting flickering issues due to abnormal voltage during cold winter temperatures, which was later traced to loose wiring connections - simple repairs restored normal operation. Regular electrical system checks can prevent these problems, especially when battery aging or charging faults may affect voltage stability. Maintaining clean and secure connection points helps sustain proper voltage levels, ensuring smooth and safe driving. Voltage abnormalities often serve as early warning signs of deeper underlying issues, and prompt troubleshooting is recommended to prevent accidents.
