The wipers turn on but only go partial across window then stop. Occasionally moving in stutter steps. Can make them move partially by twisting switch. Occasionally goes on for 1 or 2 full swipes. Motor is quiet and sounds normal when it operates. Thought it was a bad switch and replaced it. Same problem. Think it might be the intermittent relay, but don' know where that is. Any thoughts and location of intermittent relay would be appreciated.