My son is 16 will be 17 next week. He is not wanting to go to his dads. Does he have to? There is no child support involved.

It is very important that this be a decision of your son and not of you.  If, and only if, your son does not wish to visit, he must communicate this with his father.  Realize, you will be open to a claim that you unduly influenced your son. Most courts do not penalize a parent who cannot convince a child to visit. But, let's look at the other side. Your ex-husband very likely has resources and contacts that can ultimately be of advantage to your son, and if they are of advantage to your son, someday they may be of advantage to you.  The education your son gets and the contacts he makes will help him in life.  If he does well, he is better able someday to assist you.  Further, he may someday resent you for not helping him have a relationship with his father.  If you are not going to do that, get some counseling for him (and you) to be sure he does not at some level wish some contact with his father. Bottom line, encourage the contact.