High-speed UART communications with the Tech 2

The CANdi (Controller Area Network Diagnostic Interface) is an in-line cable module that works with existing GM Tech 2 components including the VCI, cables and adapters.

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 Professional Diagnostic Tool 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

Supports simultaneous communications on three CAN buses
Provides high-speed UART communications with the Tech 2
1) Connect CANdi interface to the vehicle via 12 PIN ALDL connector
2) Run and complete all GM tech2 scanner stand-alone self-test. Disconnect CANdi interface when run Tech2 scan tool self test.
3) Run VCI self test. If the VCI self-test fails, replace VCI module. Disconnect CANdi interface when run VCI self test
4) Connect the CANdi module to an existing VCI module via DLC cable, and connect VCI module with vehicle. Make sure there is good connection between scanner and vehicle. Verify that the LED on the CANdi module is flashing.
5) After well connected with vehicle and Tech2 main unit, power up the GM Tech2 scan tool, the scanner is flashing. Software update procedure will display on the screen.
6) Browse to “Tool Options” menu, select “F9 CANdi Diagnostics” option in the function list.
7) Two options available under CANdi Diagnostics menu: POST Test and Self Test
8) First run a POST Test, here is the POST Results figure. The CANdi POST result is used to determine if the module has any problems during the software upgrade or start-up sequence.
9) Then run Self Test, here is the CANdi Self Test Results figure

Perhaps the largest design change is where the cables attach to the Heavy Duty Diagnostic Tools NEXIQ USB Link 2. The original USB Link used a standard 15-pin connector, and life was good. There were a ton of aftermarket cables available, all of which sold for under $40. This included replacement 6/9 pin cables, OBDII cables, Volvo 8-pin & 14-pin, Cummins 3-pin, and many more. With the new adapter, Nexiq has changed to a 26-pin connector as shown below.