As the April 18th deadline approaches, I would recommend that if they do not send it to you in time, to use the copy they sent by mail and input manually.  By law, they should have sent one to you, by mail, on or before January 31st of each year, however, they do not have to put it online.  So with your paper copy, you can input the information.  I am including below, instructions on how to input your W-2 manually or via import (in event they send it to you online before the deadline).

https://ttlc.intuit.com/replies/3389204

Are you saying that the W-2 is not there at all? 

Or that you no longer have login rights to access it?

Have you tried to download the W-2 through TurboTax Online?

Here is more information.