I have a 2003 focus zx3 with 75,000 miles on it. I drive to work very early in the morning when it is dark outside. I notice the headlights and instrument panel dim then brighten the whole trip to work. Its almost like they are flashing. The alternator was replaced 2 years ago. The battery light only came on once for a moment in the last few months that this problem has been occuring. I had a good mechanic look at it, but he didnt find the problem. Any ideas on what could be causing this? Thanks.