UNIX for Advanced & Expert Users

Hi, I've got a file where in the middle of the record is a $ end of line character, visible only when I open the file in vi and do :set list. How to I get rid of the character in the middle and keep it at the end. The middle $ character always appears after SW, so that can be used to tag it.
Normal row - Field 1, Field2,Field3, Field 4$
Bad row - Field 1, Field2SW$,
Field3, Field 4$

awk '{ if(substr($0,length)==",") printf("%s ",$0); else print }' filename

Hi Ranjithpr;
I'm not getting the results I want... is there someway to tell the script to remove the $ character immediately after the SW and combine the two lines together.
Thanks so much for helping out.

Do the following within the file to remove SW$ .

:g/SW\$/s///

Then you can apply rangithpr's suggestion to give you a final fix

awk '{ if(substr($0,length)==",") printf("%s ",$0); else print }' filename