99 blazer rear speaker problem

I just bought a used 99 2 door blazer and the 2 speakers in the rear don't work any suggestions on what problem might be

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.