Original Opel/Vauxhall/GM CANdi diagnosis module

Opel vehicles use class 2, low-speed (10.4 K baud rate) systems. A limited number of vehicle platforms (e.g. Saturn Ion, Cadillac XLR) are equipped with the new GM LAN/CAN system. This type of application has a single-wire CAN bus for body controls, a medium-speed CAN bus for information and entertainment, and a high-speed CAN bus for powertrain (OBD II compliant modules). A new diagnostic interface—the Controller Area Network diagnostic interface (CANdi) has been developed to address these needs. The CANdi module serves as an enhancement to the Tech 2 and completes the interface necessary to communicate with future on-board computer systems.

Module operation

The CANdi is an in-line cable module that works with existing Tech 2 components including the VCI, cables and adapters. Installed, the CANdi module is fully compatible with current and past Tech 2 software. The module powers up in a way that makes it transparent to the user. This allows the existing Tech 2 software to be used with no changes when the CANdi module is installed. If a vehicle requires the use of a CANdi module, the Tech 2 will enable features specific to the module. The primary function of the CANdi module is to add CAN (controller area network) capability to the Tech 2. The following list summarizes the basic characteristics of the CANdi module:

• Supports simultaneous communications on three CAN buses
• Provides high-speed UART communications with the Tech 2

The Tech 2 controls CANdi module operation. When installed, the CANdi module does not interfere with any diagnostic procedure currently performed by the Tech 2. Use of the module does not require any physical changes to the Tech 2, cables, or adapters. The module operates transparently until activated by the Tech 2. Upon activation, the CANdi module operates under control of the Tech 2 application software loaded on the Tech 2 PCMCIA card determines all functionality.

Connecting CANdi and Tech-II

The CANdi module connects to the Tech 2 by the existing Burndy data link connector (DLC). The vehicle side connection remains unchanged using the existing adapter to interface between the DLC cable and the SAE J-1962 adapter.

See also

• Opel Tech-II page
• GM Tech-II User's Guide