Every year with the change of the seasons, I see a pattern in the failures that occur with customers cars. Everyone knows that we go from warmer to colder and back again as the seasons change, but did you know your car is adjusting to these changes?
A newer vehicles computer monitors the temperature and adjust the output of the alternator. In Hot weather the computer lowers the charging rate to keep the battery from getting too hot and boiling off the fluid in the battery. In cold weather it raises the charging rate to overcome the batteries resistance to charge when cold. The battery itself may not be very healthy but work ok when warm as warmer temeratures speed up the chemical reactions. Get it cold however and it may not be able to keep up with demand. Likewise in hot weather the build up of sulfates on the battery plates may come off and fall to the bottom which shorts out the plates and poof no start!
So if you notice a change in the sound or speed of the starter when cranking the engine,
you should have it checked out or you might just get stranded!
Hope you find this information useful!