K-Line

« Back to Glossary

📖 YOUCANIC Automotive Glossary

K-Line is a legacy serial protocol used for diagnostic communication on vehicles manufactured before CAN became mandatory in 2008. It uses ISO 9141-2 and ISO 14230 (KWP2000) standards, communicating through a single wire (pin 7 on the OBD2 connector) at 10.4 kbps. Some implementations use an L-Line (pin 15) for initialization. K-Line was common on European and Asian vehicles through the early 2000s.

For DIYers with older vehicles, K-Line support in your scanner is essential — a CAN-only scanner will not communicate. K-Line communication is slower, so data refresh and code reading take longer. Some vehicles used K-Line for body electronics even after adopting CAN for the powertrain. The YOUCANIC UCAN-II supports K-Line protocols alongside CAN for comprehensive older and newer vehicle coverage.

Synonyms:
ISO 9141, KWP2000, Keyword Protocol
« Back to Glossary