Horn honks while in reverse

What is your question?

I have a 2009 jeep liberty and I went to leave yesterday but when I put it in reverse my horn would honk and my front and rear wiper liquid would spray and the wipers would go crazy.. I do not know what this could be.

What makes this problem better or worse?

It has only happened once so I'm not sure yet.. but it happened right after it rained if that helps.

How long has your 2009 Jeep Liberty had this problem?

A few days