The correct sequence for a firmware update on ACE or ICON2 is as follows:
- The app resets the light - you should see the middle green led flash and then the left of centre green led come on
- The app sends the firmware to the light - you should see the left of centre green led change to the right of centre green led
- The light resets to complete the update - you should see the middle green led flash briefly, followed by the fuel indicator
- The app establishes contact with the light - you should see the blue led flash to indicate a Bluetooth connection has been established
The most likely issue you may experience is if the firmware update is interrupted. This can happen if the app stops unexpectedly or the phone goes out of range of the light. In this case, the light will show the left of centre green led on constantly, indicating that the light is waiting for the firmware update to resume.
In that case, please restart the app which will then resume the firmware update. In case this doesn't work, you should restart the phone. Failing both of those steps you can try an uninstall and reinstall. This will ensure you have the most up to date version.