The problem with cyber vision!! (Far Cry 3: Blood Dragon)

When you turn on the cyber vision or aim then the image disappears and only visible body parts of enemies hidden behind cover( the soldier sitting behind the box, sticking his head: aim or include cyber vision, only visible parts of the body hidden behind the box and all the rest don't.
all of this is happening only when in sight of enemies and hidden parts of bodies are visible as if I had the cyber vision!