The lastest Touch Panel Software version for 37xx is 1.23
You can check it out at Inventory page.
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or About page.
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If your version is 1.16 so you can upgrade it easily.
You just need 006B121100.GCD to put in Nuvi\.system\RemoteSW

How to get 006B121100.GCD
1). Download 3790CHNv2.50 from
Code:
Please Login or Register to see the links
2). Rename from .exe --> .rar
3). Open .rar and get 006B121100.GCD within RemoteSW folder.
4).Backup your old 006B121100.GCD within Nuvi\.system\RemoteSW
5).Replace it with the new one.
That's it.

Your 37xx will upgrade this software next time you open it.