Hello, first post here. I am trying to use my macchina a0 for the first time today and it is not showing up on my bluetooth either when plugged into a car or with the usb. I also downloaded the driver and tried to use the arduino program on my laptop to check firmware but im not sure if im doing it right. That is a little beyond my skill level and I dont know what I am doing.
What is the RGB LED doing when powered?
There are 2 guides
and a FAQ for additional help Common Issues | Macchina Docs
When I plug the dongle into either usb or obd2 the led shows red quickly and changes to green. With either power source It is not showing up on my bluetooth. I am also having another issue where an open-source program is not seeing the device on my PC, I installed silicon labs drivers on the PC and PC sees the device and assigns com5 but the 3rd party program will not see it. I don’t want to complicate the issue and this is probably completely different than the bluetooth issue.
Try using Torque or SavvyCAN Quick Start Guide | Macchina Docs on your phone; does it appear? If not, maybe try contacting here
I used arduino and found bluetooth was off on the device. I was able to turn it on and it works now.
Aha! Excellent find; I’m going to mark your post as a solution so it might help others if they run into the same issue 
I have the same issue, easy fix. Plug the macchina into a serial device. Enter ‘h’ to see all configs and menu. Enter ‘BTMODE=1’ and that should turn it on. Enter ‘h’ again to see that the changes worked, BTMODE should be ‘BTMODE=1’ where it was ‘BTMODE=0’ (off).
You need to download the arduino program on a PC and follow the guide in the firmware section of the machinna docs.
https://docs.macchina.cc/product-documentation/a0-docs/a0-firmware
If you need more help I can try to talk you through the process on arguing but I have only used it this one time to turn on the AO bluetooth