Cold crank problems

My 525i won't crank or start in mornings when it is cold outside. Do anyone know why?

some batterys give up to cold weather when they get old in the tooth

Yeah, the best thing you can do is remove the battery and take it to your friendly local auto parts store where they should test it for free. There they will tell you if it needs to be replaced or not.

If the battery checks out, then it is your cps. Crank sensor. The cold resistance is out of specs....replace it anyway, it will go bust.

Battery, cables, starter. The CPS has no bearing on an engine not cranking. This is most likely the battery. Have it tested as suggested. I agree that it is not uncommon for cold weather to kill a battery.

Oops misread. Yeah if there is no crank, then battery, fusible link and starter.

+1 on starter