Yea, I have the idea your battery is seven years old. I have NEVER expected a battery to go past three years (I am from Michigan and they just don't last very well in the cold) it just amazes me how many people will just let a battery go as if it will last forever.

If you hang around here any amount of time, you will find that old batteries will START the car fine, but, oddly enough, they seem to cause various other problems.

YEARS ago, the electrics of a car were simple, and a battery did almost nothing but turn the engine over to start it.

TODAY, the complicated electronics need a CLEAN source of power. The alternator produces a ripply output that is filtered ONLY by the battery. Old batteries don't filter well.