This Technical Information Report defines the diagnostic communication protocol Keyword Protocol 1281 (KWP1281). This document should be used in conjunction with SAE J2534-2 in order to fully implement the communication protocol in an SAE J2534 interface. Some Volkswagen of America and Audi of America vehicles are equipped with ECUs, in which a KWP1281 proprietary diagnostic communication protocol is implemented. The purpose of this document is to specify the KWP1281 protocol in enough detail to support the requirements necessary to implement the communication protocol in an SAE J2534 interface device.