i‘ve bought both of the wipersone 26 and 28
First off, I'm quite sure your van needed 28 on both sides. To install simply lift the wiper arm and push the small lever near the center of the old wiper blade(look closely), then push the old blade down. It should come right off. To install reverse the process.
that sounds like the problem unless you notice any other electrical problems with the car then it could be bad wiring.
