User Manual v1.0_EN
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professionals in various industries. Principal emphasis is placed on transport industries
such as automotive, aerospace, and commercial vehicles.
SAE J1708
SAE J1708 is a standard used for serial communications between ECUs on a heavy duty
vehicle and also between a computer and the vehicle. With respect to Open System
Interconnection model (OSI), J1708 defines the physical layer. Common higher layer
protocols that operate on top of J1708 are SAE J1587 and SAE J1922. The protocol is
maintained by SAE International.
SAE J1939
Society of Automotive Engineers standard SAE J1939 is the vehicle bus recommended
practice used for communication and diagnostics among vehicle components. It is used
in the commercial vehicle area for communication throughout the vehicle, with the
physical layer defined in ISO 11898.
J1850
Defines a serial data protocol. There are two variants- 10.4 Kbit/s (single wire, VPW) and
41.6 Kbit/s (two wire, PWM). Mainly used by US manufacturers, also known as PCI
(Chrysler, 10.4 Kbit/s), Class 2 (GM, 10.4 Kbit/s), and SCP (Ford, 41.6 Kbit/s).
OBD
On-board diagnostics (OBD) is an automotive term referring to a vehicle's self-diagnostic
and reporting capability. OBD systems give the vehicle owner or repair technician access
to the status of the various vehicle engine systems.
OBD-II diagnostic connector
The OBD-II DLC (post-1996 vehicles) is usually located under the instrument panel on
the driver side, though there are several exceptions. The SAE J1962 specification
provides for two standardized hardware interfaces, called type A and type B. Both are
female, 9-pin (2x8), D-shaped connectors, and both have a groove between the two rows
of pins.
DLC
The data link connector (DLC) is the multi-pin diagnostic connection port for automobiles,
trucks, and motorcycles used to interface a scan tool with the control modules of a given
vehicle and access on-board diagnostics and live data streams.










