Why is my phone saying battery temperature is too low

@kelumetsindlovu not sure where you are located, so we can't rule out that your phone might be to cold :-) Take it to a warmer area and try again. If the true temperature is not to cold at all, then the issues could be a failed battery sensor. Start off by replacing the battery.

Since iFixit does not yet have a specific guide for this, try something like this video to work on it.

While you work on your phone, take lots of pictures. Once you are done with it, take those pictures and create a guide for iFixit. That will help the next person that has a device with the same issues as you do. It's easy and fun to create these guides. https://ifixit.com/Guide/new The iFixit community will appreciate this.

Repair is War on Entropy!