After about 10 to 20 minutes of driving, (the longer time is during cooler weather), the battery light comes on for a minute or two and then goes off. There is a slight smell if overheated electronics, but no discernible source, and everything seems to be working properly. This has been happening for awhile with different circumstances, ac on, off heater on or off, top up or down, cruise on or off, etc. Nothing changes. Except cooler weather has moved the time light comes on back some. I would think that by now, something would quit working. Battery seems to be uneffected. Any ideas?