My car had a battery problem all of the sudden i had had no clue why. Started off with the ignition being weird and would splutter before starting. It eventually – around a day after, stop starting. Lights window and everything else worked just start didn’t start. If i left it overnight, I would have to jump the car every morning. I decided to replace the battery without testing as i did not know u could even test it. My old battery had 356 CCA in my 15 toyota. I bought a 500+ CCA and replaced it. Did i make the wrong mistake and should have tested it first to save myself $90 on the new battery. I have no idea when was the last time the car battery was replaced as well.