Why is my GPS not booting up after updating the device with new software?

This has happened with a lot of people using Garmin modules. In fact there are so many problems with the new 1490T's that people have also had to exchange over 8 copies and still no luck so they finally compromise the features and the time they have wasted and switch to the Garmin 255WT. The only option in the problem you are facing is to roll back the firmware of your Garmin GPS module to the old firmware version, but here that is not possible. So you are left with no option but to replace the GPS. Also the Garmin people are not able to find why such problems are taking place and the solutions to it, because new software's are released to make the usage better and remove existing software faults but in turn it has caused the device to stop working at all in some cases.

Also these devices are facing lots of problems like:

Continuous rebooting of the device on its own;

Bluetooth commands not recognized properly;

Stays in night mode all the time;

Problems in acquiring satellite signal,

Firmware problem such that the device stops working and also rolling back the firmware is not possible.