Wyswig editor not showing to authors in Full HTML mode for Authors
The issue is resolved as it is js error.
I fixed this issue from this solution(https://drupal.org/comment/6313896#comment-6313896).

As i am using wyswig 7.x-2.1 but the above fix is given for 7.x-2.0 which is applied clearly for my version too.
The below fig. shows that the js error.