I tested a 2005 vauxhall zafira and a Astra J 2011, vxdiag vcx nano gm can not connect to the 05 Zafira. As for the Astra J, it connected ok, but cannot read live data and lost communication continuously. Any idea how to fix this?
For Opel/Vauxhall pre-2005, it is done under tech2win software. But vxdiag teh2win does not work on Opel nor Saab.
So it won’t communicate with the 05 zafira.
For Astra J 2011, you should use GDS2 software.
Turn on ignition switch, keep engine running, select correct model and engine system, nano gm reads live data no issue.