Untitled

<!DOCTYPE html>
<html>

  <head>
    <script src="script.js"></script>
  </head>

  <body>
    <input type="button" onclick="limpiarCampos()"></input>
  </body>

</html>

// Code goes here
var firstCall = true;
function limpiarCampos() {
  alert("Ejecutando limpiarCampos()");
  if (firstCall) {
    setTimeout(limpiarCampos, 3000);
    firstCall = false;
  } else {
    firstCall = true;
  }
}