If you have a wired connection, then that may be OK.
I'd never reveal you were in the service menu if you call this in.
But to your question. The dongle only works if you see it listed at your TV model's web page. There are better options that are called WiFi to Ethernet Client Devices. These change over the years but there are dozens at amazon and in stores.
Hello: My 2012 Samsung UN55ES7100 TV will no longer connect to my home WiFi network. In the service menu, it says Wired MAC-Success, WiFi MAC-Failed. So I'm guessing the wifi card has failed. Samsung tech support/customer service were no help. My question is can I use a Samsung USB wifi dongle (WIS12ABGNX) in this TV to get back my network connection or am I SOL? Thanks, Keith.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic