When I turn the key, I hear a single click sound and engine won't start. No continuous clicking at all. When I try again after a few seconds (sometimes after a 1-2 min), then engine starts fine and the car runs as usual. Headlights and wipers perform as usual at idle probably suggesting that battery charge is fine. Noticed this last evening when going out to run errands after driving 15 miles from work. Any suggestions as to where a problem might lie?