This document is intended to satisfy the requirements of an OBD scan tool as required by U.S. On-Board
Diagnostic (OBD) regulations.
The document specifies:
a. A means of establishing communications between an OBD-equipped vehicle and external test
b. A set of diagnostic services to be provided by the external test equipment in order to exercise the
services defined in SAE J1979-2,
c. Conformance criteria for the external test equipment.
Rationale: J1979-2 will document the UDS based service modes intended to replace/enhance the classic J1979-1 services. An equivalent J1978-2 document will specify the scan tool requirements to interface with J1979-2.