Need to REPAIR a 3790T

If you switch off all lights in the house, make it very dark and press button on device do you see some faint light from the display ?
Have you tried holding power button down for more than 30 seconds ? (with good battery installed)
Garmin don't fix boards at local branches. They will probably offer you an exchange refurbished unit at a reduced price.
If they do you might be able to choose 3490 or 3590.

I agree.
The device is faulty in someway.
Still looking for a service shop down here.
Thanks !

For some reason, my comment disapeared.

Yes, it seems that the device is malfunctioning. I will look for a service shop.

Thanks !

I took the GPS to a shop.

It seems that the electrical contact, where the USB cable connects was having some sort of break wire inside. The guys claims he soldered and the GPS is working fine now.

At least, until now.

Thanks for all comments.

When God created the world he made it without contact but then he recognized him error and added contact :)
Humor of Electrics!